Integrated energy storage system and control method thereof

Abstract

The application discloses an integrated energy storage system and a control method thereof, adopts a structure of "low-high temperature double cycle + plate exchange + distributed top-mounted cold machine", a low-temperature cycle loop is used for absorbing battery heat and circulating in a high-temperature environment, a high-temperature cycle loop is used for providing heat for the battery in a low-temperature environment, and further exchanges heat with a refrigerant circulating unit; the secondary heat exchange mode can realize stable operation in a wide temperature range, greatly expands the deployment region of the energy storage system, and the heat exchange efficiency is much higher than that of a pure air cooling mode; moreover, the dangerous refrigerant circuit and the battery circuit can be completely isolated, and the safety is high; in addition, the distributed cold machine structure provides exclusive heat management for the battery cluster of each subsystem, completely solves the problem of uneven temperature in the container, and significantly reduces the operation energy consumption; a group string type PCS is adopted, one cluster is managed, inter-cluster circulation is eliminated, and the PCS has excellent network construction function and overload adaptation capacity.

Description

Technical Field

[0001] This invention relates to the field of new energy storage system technology, specifically to an integrated energy storage system and its control method. Background Technology

[0002] With the advancement of the "dual carbon" goals, the scale and number of electrochemical energy storage power stations have grown rapidly. Integrated energy storage systems have become the mainstream form due to their high integration and convenient deployment. However, the heat generation and thermal runaway safety issues of their internal batteries have always been a technical bottleneck in the industry. Furthermore, current energy storage technologies are developing towards high energy density, high safety, and high grid support capabilities, but existing technical solutions are fragmented in terms of system integration, often focusing only on one aspect, resulting in shortcomings in overall performance.

[0003] Existing integrated energy storage systems offer rapid installation and convenient centralized management, but their thermal management and safety still need improvement, mainly in the following aspects:

[0004] 1. Using the traditional air-cooling system: This system uses air as the cooling medium. It has a simple structure but low heat exchange efficiency and poor temperature uniformity in the container. It is difficult to meet the heat dissipation requirements of large-capacity, high-power-density battery clusters. In particular, it is not effective in high-temperature environments, which leads to faster battery life degradation.

[0005] 2. Using a centralized liquid cooling system: A high-power air conditioner or chiller unit is used to cool the entire container. Although the heat exchange efficiency is higher than that of air cooling, there is a "barrel effect", that is, the system cooling capacity must be designed according to the needs of the hottest battery cluster, resulting in energy waste; moreover, the air duct design is complicated, and battery modules far from the air outlet are prone to overheating; once the central air conditioning fails, the entire system will face the risk of thermal runaway, resulting in low reliability.

[0006] 3. Conventional direct-cooling liquid cooling system mode: The refrigerant evaporates and absorbs heat directly in the cold plate inside the battery pack. Although it is highly efficient, the system piping is complex, the refrigerant charge is large, there is a risk of leakage, and the requirements for the sealing and insulation of the battery pack are extremely high, making maintenance difficult.

[0007] Furthermore, existing technologies pose risks of corrosion and leakage. This is primarily manifested in the increased conductivity of the coolant in the liquid cooling circuit over time, leading to ionization corrosion and leakage, thus impacting the long-term reliability of the system. Additionally, current thermal management strategies are simplistic, with most systems focusing only on battery heat dissipation in summer (high-temperature management) and neglecting the need for battery heating and insulation in low-temperature environments. This results in a sharp drop in battery performance or even renders the battery unusable in cold regions. Moreover, the timing control of fire emergency response plans in existing energy storage systems is inadequate, posing a risk. Summary of the Invention

[0008] This invention provides an integrated energy storage system and its control method, aiming to improve heat dissipation efficiency and stability. This invention is achieved through the following technical solution:

[0009] A first aspect of the present invention provides an integrated energy storage system, including a container body, and further including a battery module, a thermal management module, an electrical module, a string PCS module, and a step-up transformer module integrated into the container body; the battery module includes multiple independent battery clusters, and the multiple independent battery clusters are arranged in a string structure to form at least two battery cluster sub-arrays; characterized in that:

[0010] The thermal management component includes a coolant circulation unit and a refrigerant circulation unit; the refrigerant circulation unit includes at least two distributed overhead chillers, each overhead chiller corresponding to one battery cluster subarray; the coolant circulation unit includes a low-temperature circulation loop and a high-temperature circulation loop, the low-temperature circulation loop including a liquid-cooled plate that cooperates with the heat exchange of the battery assembly and a low-temperature side-plate heat exchanger that cooperates with the heat exchange of the refrigerant circulation unit, the high-temperature circulation loop including a liquid-cooled plate that cooperates with the heat exchange of the battery assembly and a high-temperature side-plate heat exchanger that cooperates with the heat exchange of the refrigerant circulation unit; the string PCS component is configured with one string-type network PCS for each battery cluster.

[0011] The integrated energy storage system provided by the above technical solution has the following advantages: It adopts an architecture of "low-temperature dual-cycle + plate heat exchanger + distributed top-mounted chiller." The low-temperature cycle loop absorbs and circulates battery heat in high-temperature environments, while the high-temperature cycle loop provides heat to the battery in low-temperature environments, enabling stable operation over a wide temperature range of -30℃ to +50℃, greatly expanding the deployment area of ​​the energy storage system. Furthermore, the secondary heat exchange method of "liquid cooling + heat exchange plate heat exchange" allows the highly efficient liquid cooling system to quickly remove a large amount of heat, significantly suppressing the spread of thermal runaway, with efficiency far exceeding that of simple air cooling. Moreover, the "liquid cooling..." The secondary heat exchange method of "+heat exchange plate heat exchange" completely isolates the dangerous refrigerant circuit from the battery circuit. Even if refrigerant leakage occurs, it will not affect the battery system, ensuring high safety. Furthermore, the distributed refrigeration unit architecture provides dedicated thermal management for each battery cluster in the subsystem, completely solving the problem of uneven temperature within the container and extending battery life. The output power of the corresponding refrigeration unit can be independently adjusted according to the actual temperature and heat generation of each battery cluster subarray, avoiding "overcooling" and significantly reducing operating energy consumption. Moreover, if one top-mounted refrigeration unit fails, only the corresponding battery cluster subarray is affected, while other clusters can continue to operate normally, greatly improving system reliability. Finally, the use of a string-type network PCS enables one-cluster-one-management, eliminating inter-cluster circulation, and the PCS has excellent overload adaptability for network functional units.

[0012] As a preferred technical solution, the container body has a battery compartment, an electrical compartment, and a converter and booster compartment; the battery modules and thermal management components are disposed in the battery compartment, and each battery cluster subarray of the battery modules is disposed in one of the battery compartments; the electrical components are disposed in the electrical compartment; the string PCS modules and booster transformer modules are disposed in the converter and booster compartment, or the booster transformer modules are disposed in the converter and booster compartment, and the string PCS modules are disposed in the battery compartment.

[0013] The advantages of the above-mentioned preferred solution are as follows: the separate compartments for battery components, electrical components, string PCS components and step-up transformer components facilitate maintenance and enhance safety; furthermore, by setting each battery cluster subarray of the battery component in one of the battery compartments, flexible temperature control by zone can be achieved, enabling precise control.

[0014] As a preferred technical solution, each of the top-mounted chillers has two independent chiller side plate heat exchangers, one of which is a refrigeration plate heat exchanger that exchanges heat with the low-temperature circulation loop, and the other is a heating plate heat exchanger that exchanges heat with the high-temperature circulation loop.

[0015] The advantages of the above-mentioned preferred solution are that the two chiller side plate heat exchangers are used in conjunction with the low-temperature circulation loop and the high-temperature circulation loop respectively for heat exchange, making the use more flexible and having greater heat exchange efficiency.

[0016] As a preferred technical solution, the low-temperature circulation loop and the high-temperature circulation loop are equipped with a deionization device and an online conductivity detection sensor, which are respectively electrically connected to the electrical components.

[0017] The advantages of the above preferred solution are: the coolant is continuously purified by the deionization device to maintain its low conductivity; or, the conductivity detection sensor monitors the conductivity of the coolant in the corresponding circuit in real time, and when the conductivity exceeds the standard, the linkage electrical components alarm or control the deionization device to start, effectively preventing pipeline corrosion and insulation performance degradation.

[0018] As a preferred technical solution, the thermal management component further includes a cabinet air conditioner installed in the electrical compartment and an energy storage air conditioner installed in the battery compartment.

[0019] The advantages of the above-mentioned preferred solution are as follows: Independently configured cabinet air conditioners are specifically designed to dissipate heat from the integrated control cabinet, UPS, and other electrical equipment within the electrical compartment, ensuring the reliability of core control components. Furthermore, each battery compartment is equipped with a separate energy storage air conditioner, independent of the thermal management components. This energy storage air conditioner can dehumidify the air within the battery compartment in high-humidity environments, achieving decoupling between battery cooling and compartment dehumidification. Specifically, the "liquid cooling + heat exchange plate" section focuses on addressing the primary challenge of battery heat generation, while the independent energy storage air conditioner handles ambient humidity. This decoupling design avoids over-cooling the battery for dehumidification, resulting in more precise control, higher energy efficiency, and fundamentally eliminating the risk of condensation. It complements the liquid cooling system, which is primarily responsible for heat generation and dissipation, enhancing the long-term operational safety of the system.

[0020] As a preferred technical solution, the electrical components include a cabinet with a built-in main power distribution molded case circuit breaker, main power meter, and uninterruptible power supply, as well as an energy storage system ECU for performing DI signal acquisition, BMS management, thermal management monitoring, component monitoring, and human-machine interaction.

[0021] In the preferred embodiment described above, an intelligent unified controller ECU is used as the core of the system. The operating status and coordination strategies of the battery system, thermal management system, fire protection components and PCS are integrated and managed through a communication network to achieve intelligent local control based on the ECU-brain.

[0022] As a preferred technical solution, the integrated energy storage system also includes a fire-fighting component integrated into the container body. The fire-fighting component includes fire detectors, fire extinguishing devices, a data concentrator, and a fire alarm control device. The fire detectors include battery pack fire detectors and battery compartment fire detectors arranged in two levels. The fire extinguishing devices include battery compartment fire extinguishing agent nozzles, battery pack fire extinguishing agent nozzles, and a battery compartment water sprinkler system arranged in three levels. The data concentrator collects the detection signals from multiple fire detectors and transmits them to the fire alarm control device, which judges the fire situation and controls the action of the fire extinguishers.

[0023] The advantages of the above-mentioned preferred scheme are as follows: the detection and spraying strategy adopts a three-level protection scheme of "Pack-level detection + compartment-level detection" and "compartment-level extinguishing agent nozzle + Pack-level extinguishing agent nozzle (spray into the bag) + water spraying system"; making fire detection more timely and sensitive, and the fire extinguishing level can be controlled in stages.

[0024] As a preferred technical solution, the tripping electrical control circuit of the fire alarm control device that controls the action of the fire extinguisher is equipped with a power-delay time relay. The power-delay time relay is used to control the tripping of the battery cluster BMS power switch, so that it performs the power cut-off after a delay of several seconds after the fire action signal is issued.

[0025] The advantages of the above-mentioned preferred solution are as follows: by setting a power-on delay type time relay, it is ensured that before the final power-off, the ECU has enough time to reliably send a disconnection command to the DC circuit breaker in the high-voltage box of the battery cluster via, for example, RS485 communication, to prioritize the disconnection of the high-voltage DC circuit and eliminate the risk of extinguishing the fire while the circuit is energized.

[0026] A second aspect of the present invention addresses the technical solution of providing a deionization device and an online conductivity detection sensor in the low-temperature and high-temperature circulation loops; it provides a control method for the aforementioned integrated energy storage system, characterized in that it includes:

[0027] Based on the battery temperature and ambient temperature, the coolant circulation unit and refrigerant circulation unit are controlled to automatically switch between cooling, heating, and natural cooling modes. The electrical components execute the following coordinated strategies: independently controlling the energy storage air conditioner to regulate humidity based on the battery compartment humidity, and independently controlling the cabinet air conditioner to regulate temperature based on the electrical compartment temperature; simultaneously, coordinating the output of the grid-type PCS according to grid dispatch instructions or local measurement signals to perform frequency regulation, voltage regulation, and inertia response.

[0028] The control method for the integrated energy storage system provided by the above technical solution has the following advantages: It adopts an architecture of "low-high temperature dual-cycle + plate heat exchanger + distributed rooftop chiller," enabling stable operation of thermal management under multiple modes and wide temperature ranges, greatly expanding the deployment area and adaptability of the energy storage system. Furthermore, it employs a string-type grid-connected PCS, possessing ten major functions including weak grid adaptation, short-term overload, continuous fault ride-through, phase angle jump tolerance, grid-connected / off-grid switching, black start, fast frequency regulation, inertia response, damping control, and dynamic voltage regulation. It comprehensively supports the dynamic stability, rapid recovery, and reconstruction of the power grid under various large and small disturbances, and can autonomously construct and maintain grid voltage and frequency, possessing strong grid support capabilities.

[0029] A third aspect of the present invention addresses the technical solution of providing a deionization device and an online conductivity detection sensor in the low-temperature and high-temperature circulation loops; it provides a control method for the aforementioned integrated energy storage system, characterized in that it includes:

[0030] Based on the battery temperature and ambient temperature, the coolant circulation unit and refrigerant circulation unit are automatically switched between cooling, heating, and natural cooling modes. The deionization device is automatically or prompted to start / stop to purify the coolant online, based on the online conductivity monitoring value of the coolant circuit of the coolant circulation unit detected by the online conductivity detection sensor.

[0031] The control method for the integrated energy storage system provided by the above technical solution has the following advantages: by adopting the architecture of "low-temperature dual-cycle + plate heat exchanger + distributed rooftop chiller", it can achieve stable operation of thermal management under multiple modes and wide temperature range, which greatly expands the deployment area and adaptability of the energy storage system; in addition, by continuously purifying through the deionization device or by starting the purification operation under the trigger of the conductivity detection sensor monitoring signal, it effectively prevents pipeline corrosion and insulation performance degradation.

[0032] A fourth aspect of the present invention addresses a technical solution for providing a power-on delay type time relay in the tripping electrical control circuit of the fire alarm control device controlling the action of the fire extinguisher; it also provides a control method for the aforementioned integrated energy storage system, characterized in that it includes: controlling the coolant circulation unit and the refrigerant circulation unit to automatically switch between cooling, heating, and natural cooling modes based on the battery temperature and ambient temperature; wherein the following fire emergency steps are taken:

[0033] S100: Receives fire alarm action signals from the fire-fighting components for a level 3 fire alarm;

[0034] S200 sends a stop command to the PCS and starts a preset delay timer;

[0035] S300: Before the delay timer expires, the ECU sends a disconnection command to the DC circuit breaker in the high-voltage box of each battery cluster.

[0036] S400. After the delay timer expires, the BMS control power supply is cut off.

[0037] The control method for the integrated energy storage system provided by the above technical solution has the following advantages: Adopting an architecture of "low-high temperature dual-cycle + plate heat exchanger + distributed rooftop chiller," it can achieve stable operation of thermal management under multiple modes and a wide temperature range, greatly expanding the deployment area and adaptability of the energy storage system. Furthermore, a power-on delay time relay is used to control the tripping of the BMS power switch, causing it to delay for several seconds after the fire alarm signal is issued before executing the power cut-off. This ensures that before the final power cut-off, the ECU has sufficient time to reliably send a disconnection command to the DC circuit breaker in the high-voltage box via RS485 communication, prioritizing the disconnection of the high-voltage DC circuit and eliminating the risk of energized fire suppression. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a main structural layout diagram of the integrated energy storage system provided in a specific embodiment of the present invention.

[0040] Figure 2 This is a layout diagram of the converter booster chamber in the integrated energy storage system provided by a specific embodiment of the present invention.

[0041] Figure 3 This is an example diagram of the thermal management component in the integrated energy storage system provided in a specific embodiment of the present invention.

[0042] Figure 4 This is a fire control-package level action logic diagram in an integrated energy storage system provided by a specific embodiment of the present invention.

[0043] Figure 5 This is a fire control-cabin-level action logic diagram in an integrated energy storage system provided by a specific embodiment of the present invention.

[0044] Figure 6 This is a fire control-electric compartment action logic diagram in an integrated energy storage system provided by a specific embodiment of the present invention.

[0045] Figure 7 This is a fire-fighting action safety control loop diagram provided in a specific embodiment of the present invention for an integrated energy storage system. Detailed Implementation

[0046] To make the technical solution of the present invention clearer and its technical advantages more apparent, the technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of the present invention.

[0047] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. For ease of explanation, the orientations are defined in conjunction with the drawings. These orientation definitions are merely for the purpose of clearly describing the relative positional relationships and are not intended to limit the actual orientation of the product or device during production, use, or sale. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Moreover, in the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0048] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0049] Combination Figure 1 and Figure 2 As shown, as a basic implementation, this embodiment provides an integrated energy storage system, including a container body 100, and also including a battery module 10, a thermal management component, an electrical component, a string PCS component 40, and a step-up transformer component integrated in the container body 100; the battery module 10 includes multiple independent battery clusters, and the multiple independent battery clusters form at least two battery cluster sub-arrays in a string structure, and the string PCS component 40 is configured with one string grid PCS for each of the battery clusters.

[0050] In this embodiment, the thermal management component includes a coolant circulation unit and a refrigerant circulation unit; the refrigerant circulation unit includes at least two distributed overhead chillers, each overhead chiller corresponding to a battery cluster subarray; the coolant circulation unit includes a low-temperature circulation loop and a high-temperature circulation loop, the low-temperature circulation loop includes a liquid-cooled plate that cooperates with the battery assembly for heat exchange and a low-temperature side-plate heat exchanger that cooperates with the refrigerant circulation unit for heat exchange, and the high-temperature circulation loop includes a liquid-cooled plate that cooperates with the battery assembly 10 for heat exchange and a high-temperature side-plate heat exchanger that cooperates with the refrigerant circulation unit for heat exchange.

[0051] The integrated energy storage system provided in the above embodiments adopts an architecture of "low-temperature dual-cycle + plate heat exchanger + distributed top-mounted chiller". The low-temperature cycle loop is used to absorb and circulate battery heat in high-temperature environments, while the high-temperature cycle loop is used to provide heat to the battery in low-temperature environments. It can achieve stable operation over a wide temperature range of -30℃ to +50℃, greatly expanding the deployment area of ​​the energy storage system. In addition, the secondary heat exchange method of "liquid cooling + heat exchanger plate heat exchange" allows the highly efficient liquid cooling system to quickly remove a large amount of heat, which has a significant effect on suppressing the spread of thermal runaway and is far more efficient than simple air cooling. Moreover, the "liquid cooling + heat exchanger plate heat exchanger" method... The secondary heat exchange method completely isolates the hazardous refrigerant circuit from the battery circuit, ensuring high safety even if refrigerant leaks. Furthermore, the distributed refrigeration architecture provides dedicated thermal management for each battery cluster in the subsystem, completely resolving the issue of uneven temperature within the container and extending battery life. The output power of the corresponding refrigeration unit can be independently adjusted based on the actual temperature and heat generation of each battery cluster subarray, avoiding overcooling and significantly reducing operating energy consumption. Moreover, if one top-mounted refrigeration unit fails, only the corresponding battery cluster subarray is affected, while other clusters continue to operate normally, greatly improving system reliability. Finally, the use of a string-type network PCS enables one-cluster-one-management, eliminating inter-cluster circulation, and the PCS has excellent overload adaptability for network functional units.

[0052] In a preferred embodiment, the container body 100 includes a battery compartment 101, an electrical compartment 102, and a converter / boost compartment 103. Battery modules 10 and thermal management components are disposed in the battery compartment 101, with each battery cluster subarray of the battery module 10 correspondingly disposed within one battery compartment 101. Electrical components are disposed in the electrical compartment 102. String PCS modules 40 and boost transformer modules are disposed in the converter / boost compartment 103, or, alternatively, the boost transformer modules are disposed in the converter / boost compartment 103, and the string PCS modules 40 are disposed in the battery compartment 101. This compartmentalized arrangement of the battery modules, electrical components, string PCS modules, and boost transformer modules facilitates maintenance and enhances safety. Furthermore, by further assigning each battery cluster subarray of the battery module to a corresponding battery compartment, flexible zoned temperature control can be achieved, enabling precise control.

[0053] As described above, the battery assembly 10 includes multiple independent battery clusters, and each battery cluster can further include multiple battery packs. As a specific example, the specific configuration of the battery clusters in this embodiment is as follows:

[0054] Battery selection and packing: 314Ah high-capacity lithium iron phosphate cells are used. Each battery pack is packed in a 1P104S configuration, consisting of 104 cells connected in series, with a rated voltage of 332.8V (based on 3.2V cells).

[0055] Battery cluster configuration: Four of the above-mentioned battery packs are connected in series to form a battery cluster, with a rated voltage of 1331.2V. Twelve such battery clusters are arranged in parallel within the entire container, with a total capacity of approximately 5MWh; every six battery clusters form a battery cluster subarray.

[0056] Battery thermal management interface configuration: Each battery pack integrates a set of brazed aluminum alloy liquid cooling plates. The flow channels of the cooling plates are optimized to ensure large-area contact with the battery cells and uniform heat exchange.

[0057] The above configuration achieves high energy density and uniform voltage level in a single compartment.

[0058] In the coolant circulation unit described in the above embodiments, the low-temperature circulation loop may include a low-temperature pump, low-temperature piping, a liquid cooling plate within the battery pack, and a low-temperature side-plate heat exchanger. This loop is filled with an antifreeze coolant such as ethylene glycol aqueous solution, used to absorb battery heat and circulate it in high-temperature environments. The high-temperature circulation loop may include a high-temperature pump, high-temperature piping, a PTC heater, and a high-temperature side-plate heat exchanger; this high-temperature circulation loop is used to provide heat to the battery in low-temperature environments.

[0059] The refrigerant circulation unit described in the above embodiments adopts a distributed top-mounted multi-unit architecture, that is, multiple compact air-cooled plate chillers are arranged as top-mounted chillers 21 on the top of the battery compartment 101 of the container body 100. In a preferred embodiment, the top-mounted chillers 21 are two 13kW air-cooled top-mounted plate chillers. Each top-mounted chiller 21 is independently connected to and serves six battery clusters through piping, that is, one chiller corresponds to one battery cluster sub-array. Each top-mounted chiller has two independent chiller side plate heat exchangers, one of which is a refrigeration plate heat exchanger (hereinafter referred to as refrigeration plate heat exchanger) that exchanges heat with the low-temperature circulation loop, and the other is a heating plate heat exchanger (hereinafter referred to as heating plate heat exchanger) that exchanges heat with the high-temperature circulation loop; the two chiller side plate heat exchangers cooperate with the low-temperature circulation loop and the high-temperature circulation loop for heat exchange respectively, which makes the use more flexible and has greater heat exchange efficiency. The refrigerant circulation unit also includes an outdoor unit (one or more variable frequency compressors), which is located outside the container body 100 and connected to all roof-mounted chillers through refrigerant pipelines to form a closed-loop multi-split system.

[0060] It is understood that the main feature of the above embodiments lies in the "low-high temperature dual circulation + plate heat exchanger + distributed top-mounted chiller" architecture formed by the cooperation of the refrigerant circulation unit and the coolant circulation unit; as for the specific implementation methods of the refrigerant circulation unit and the coolant circulation unit, there can be many other specific implementation methods, for example, Figure 3 A specific example diagram of the heat exchange coordination between a refrigerant circulation unit and a coolant circulation unit is provided.

[0061] Based on the above description, the working mode of the thermal management component in this embodiment is as follows:

[0062] Summer Cooling Mode: When the battery temperature exceeds the set upper limit, the low-temperature circulation loop and refrigerant circulation unit are activated. At this time, the battery heat is transferred to the low-temperature coolant through the liquid cooling plate. The high-temperature coolant flows through the cooling plate heat exchanger of the indoor unit, where it transfers heat to the refrigerant. The cooled coolant then returns to the battery pack to complete the circulation. The refrigerant carries the heat to the outdoor unit and dissipates it into the atmosphere.

[0063] Winter heating mode: When the battery temperature is below the set lower limit, the high-temperature circulation loop and refrigerant circulation unit are activated (operating in heat pump mode or switching via a four-way valve). At this time, the refrigerant releases heat at the heating plate heat exchanger of the indoor unit, heating the coolant in the high-temperature loop. The heated coolant is further heated by the PTC heater (optional auxiliary heating) and then flows into the liquid cooling plate of the battery pack to heat the battery.

[0064] Spring and Autumn Natural Cooling Mode: When the ambient temperature is suitable, only the low-temperature circulation loop can be run, using the dry cooler outside the container or natural air cooling to dissipate heat from the coolant. At this time, the refrigerant circulation unit does not start, achieving zero-power cooling.

[0065] In a preferred embodiment, the low-temperature circulation loop and the high-temperature circulation loop are equipped with deionization devices and online conductivity sensors, which are electrically connected to the electrical components. The deionization devices continuously purify the coolant to maintain its low conductivity; alternatively, the conductivity sensors monitor the coolant conductivity in the corresponding loops in real time. When the conductivity exceeds the standard, the electrical components are triggered to alarm or to activate the deionization devices, effectively preventing pipeline corrosion and degradation of insulation performance.

[0066] In a preferred embodiment, the thermal management component further includes a rack-mounted air conditioner 22 disposed in the electrical compartment 102. The independently configured rack-mounted air conditioner 22 is specifically designed to dissipate heat from the integrated control cabinet, UPS, and other electrical equipment within the electrical compartment, ensuring the reliability of the core control components.

[0067] In a preferred embodiment, the thermal management component further includes an energy storage air conditioner 23 corresponding to each of the battery compartments. Each battery compartment is equipped with an energy storage air conditioner 23, which operates independently of the thermal management component. This energy storage air conditioner 23 can dehumidify the air inside the battery compartment in high-humidity environments, achieving decoupling between battery cooling and compartment dehumidification. Specifically, the "liquid cooling + heat exchange plate" section focuses on addressing the primary challenge of battery heat generation, while the independent energy storage air conditioner 23 handles ambient humidity. This decoupling design avoids over-cooling the battery for dehumidification, resulting in more precise control, higher energy efficiency, and fundamentally eliminating the risk of condensation. It complements the coolant circulation unit, which is primarily responsible for heat generation and dissipation, enhancing the long-term safety of the system.

[0068] As mentioned above, a string-type PCS is used to achieve one-cluster-one-management, eliminating inter-cluster circulating currents. Furthermore, the PCS possesses excellent overload adaptability for grid construction functions. Specifically, the PCS fully supports grid construction functions, possessing ten major functions including weak grid adaptation, short-time overload, continuous fault ride-through, phase angle jump tolerance, grid-connected / off-grid switching, black start, fast frequency regulation, inertia response, damping control, and dynamic voltage regulation. It comprehensively supports the dynamic stability, rapid recovery, and reconstruction of the power grid under various large and small disturbances, and can autonomously construct and maintain grid voltage and frequency, possessing strong grid support capabilities. In addition, the PCS has short-time overload capability, preferably meeting 3 times the overload requirement to cope with grid impacts and fault conditions.

[0069] The PCS, through its built-in control algorithm, supports and fully activates the following ten network construction functions in both hardware and software:

[0070] 1. Weak grid adaptability: Stable operation under extremely weak power grids with a short-circuit ratio (SCR) < 1.5.

[0071] 2. Short-time overload: It has an overload capacity of 300% of the rated current for 10 seconds.

[0072] 3. Continuous fault ride-through: When the grid voltage drops to 0%, it can withstand a fault for no less than 150ms and can ride through multiple faults consecutively.

[0073] 4. Phase angle jump tolerance: It can tolerate power grid phase angle jumps within ±90°.

[0074] 5. On-line and off-line handover: Seamless on-line and off-line handover can be achieved in less than 100ms.

[0075] 6. Black start: When the power grid is without power, it can automatically start to establish voltage and frequency for the local power grid.

[0076] 7. Fast frequency modulation: Frequency modulation response time is less than 100ms.

[0077] 8. Inertia Response: It can simulate the inertia of a synchronous machine, provide damping, and suppress the rate of frequency change.

[0078] 9. Damping control: Effectively suppresses subsynchronous oscillations of the power grid.

[0079] 10. Dynamic voltage regulation: Dynamically outputs reactive power and regulates voltage according to the grid demand.

[0080] In a preferred embodiment, the electrical components include a cabinet that integrates a main power distribution molded case circuit breaker, a main power meter, and an uninterruptible power supply, as well as an energy storage system local controller (ECU) for performing DI signal acquisition, BMS management, thermal management monitoring, component monitoring, and human-machine interaction.

[0081] The data acquisition and control functions of the ECU are described below:

[0082] DI signal acquisition: Acquire switch signals such as water immersion, emergency stop, main switch status, UPS input switch status, BMS power switch status, surge arrester fault, door open status, and fire fault;

[0083] BMS Management: Summarizes BCU and BMU data, calculates SOC / SOH / SOP, executes balancing strategies, performs insulation detection and cluster high-voltage management, and executes battery anomaly alarms and protection;

[0084] Thermal management component monitoring: Collects data such as operating status, temperature, and faults of cabinet air conditioners, energy storage air conditioners, and rooftop chillers via RS485 communication;

[0085] Monitoring of other equipment: Data from the main power meter, fire alarm controller, PCS power meter, UPS, etc. are collected via RS485 / RS232;

[0086] Human-machine interaction: The ECU is equipped with a touch screen controller for status viewing, real-time data monitoring, parameter configuration, and manual control.

[0087] In the preferred embodiment described above, an intelligent unified controller ECU is used as the core of the system. The operating status and coordination strategies of the battery system, thermal management system, fire protection components and PCS are integrated and managed through a communication network to achieve intelligent local control based on the ECU-brain.

[0088] As a further preferred embodiment, the integrated energy storage system provided in this embodiment also includes a fire-fighting component integrated into the container body 100. The fire-fighting component includes fire detectors, fire extinguishing devices, a data concentrator, and a fire alarm control device. The fire detectors include battery pack fire detectors and battery compartment fire detectors deployed in two levels. The fire extinguishing devices include battery compartment fire extinguishing agent nozzles, battery pack fire extinguishing agent nozzles, and a battery compartment water sprinkler system deployed in three levels. The data concentrator collects the detection signals from multiple fire detectors and transmits them to the fire alarm control device, which assesses the fire situation and controls the action of the fire extinguishers. Specifically, perfluorohexanone micro-nozzles are installed inside each battery pack; perfluorohexanone all-area nozzles are installed on the top of the battery compartment; and a water sprinkler system is installed on the top of the battery compartment as a final barrier to prevent the fire from spreading to the container structure.

[0089] Specifically, the package-level action logic diagram of fire control in the integrated energy storage system provided in this embodiment is as follows: Figure 4 As shown, the cabin-level action logic diagram for fire control is as follows: Figure 5 As shown, the electrical control module's operational logic diagram for fire protection is as follows: Figure 6 As shown.

[0090] In the preferred embodiment described above, the detection and spraying strategy adopts a three-level protection scheme of "Pack-level detection + cabin-level detection" and "Pack-level extinguishing agent nozzle (spraying into the pack) + cabin-level extinguishing agent nozzle + water spraying system"; which makes fire detection more timely and sensitive, and the fire extinguishing level can be controlled in stages.

[0091] In a preferred embodiment, the tripping electrical control circuit of the fire alarm control device that controls the action of the fire extinguisher is equipped with a power-delay time relay. The power-delay time relay is used to control the tripping of the battery cluster BMS power switch, so that it performs the power cut-off after a delay of several seconds after the fire action signal is issued.

[0092] Combination Figure 7As shown, the specific operation process is as follows: When the system determines that it is a Level 3 fire alarm (the most severe level) and activates the perfluorohexanone spray, the fire alarm controller simultaneously sends a "fire trip" signal. This signal is immediately sent to the PCS, causing it to stop immediately and disconnect the AC side contactor; at this time, the contacts of the time relay begin to delay (set to 3 seconds in this embodiment); within this 3-second window, the ECU sends an emergency trip command to the DC circuit breaker in the high-voltage box of each battery cluster via RS485 communication; since the BMS power supply has not yet been cut off, the DC circuit breaker can reliably perform the trip operation, completely cutting off the high-voltage DC circuit inside the battery cluster; after the 3-second delay ends, the time relay activates, cutting off the BMS control power supply; thus, the system completes the safety sequence of "first cutting off high voltage, then cutting off control power," ensuring that there is no high voltage inside the battery cluster when the extinguishing agent is released, greatly improving fire extinguishing efficiency and safety.

[0093] In the preferred embodiment described above, by setting a power-on delay time relay, it is ensured that before the final power-off, the ECU has enough time to reliably send a disconnect command to the DC circuit breaker in the high-voltage battery box via, for example, RS485 communication, to prioritize cutting off the high-voltage DC circuit and eliminate the risk of extinguishing the fire while the circuit is energized.

[0094] Furthermore, this embodiment also addresses the technical solution of installing deionization devices and online conductivity detection sensors in the low-temperature and high-temperature circulation loops; and provides a control method for the aforementioned integrated energy storage system, including: controlling the coolant circulation unit and refrigerant circulation unit to automatically switch between cooling, heating, and natural cooling modes based on battery temperature and ambient temperature; wherein the electrical components execute the following cooperative strategy: independently controlling the energy storage air conditioner to adjust humidity based on battery compartment humidity, and independently controlling the cabinet air conditioner to adjust temperature based on electrical compartment temperature; simultaneously, coordinating the output of the grid-type PCS according to grid dispatch instructions or local measurement signals to perform frequency regulation, voltage regulation, and inertia response.

[0095] The control method for the integrated energy storage system provided by the above technical solution has the following advantages: It adopts an architecture of "low-high temperature dual-cycle + plate heat exchanger + distributed rooftop chiller," enabling stable operation of thermal management under multiple modes and wide temperature ranges, greatly expanding the deployment area and adaptability of the energy storage system. Furthermore, it employs a string-type grid-connected PCS, possessing ten major functions including weak grid adaptation, short-term overload, continuous fault ride-through, phase angle jump tolerance, grid-connected / off-grid switching, black start, fast frequency regulation, inertia response, damping control, and dynamic voltage regulation. It comprehensively supports the dynamic stability, rapid recovery, and reconstruction of the power grid under various large and small disturbances, and can autonomously construct and maintain grid voltage and frequency, possessing strong grid support capabilities.

[0096] Furthermore, this embodiment also addresses the technical solution of incorporating deionization devices and online conductivity sensors in the low-temperature and high-temperature circulation loops; and provides a control method for the aforementioned integrated energy storage system, comprising: controlling the coolant circulation unit and refrigerant circulation unit to automatically switch between cooling, heating, and natural cooling modes based on the battery temperature and ambient temperature; wherein, based on the online conductivity monitoring value of the coolant circuit of the coolant circulation unit detected by the online conductivity sensor, the deionization device is automatically or prompted to be started or stopped to purify the coolant online.

[0097] The beneficial effects of the above control method are as follows: by adopting the architecture of "low and high temperature dual circulation + plate heat exchanger + distributed top-mounted chiller", it is possible to achieve stable operation of thermal management under multiple modes and wide temperature range, which greatly expands the deployment area and adaptability of the energy storage system; in addition, by continuously purifying through the deion device or by starting the purification operation under the trigger of the monitoring signal of the conductivity detection sensor, pipeline corrosion and insulation performance degradation are effectively prevented.

[0098] Finally, this embodiment also addresses the technical solution of setting a power-delay type time relay in the tripping electrical control circuit of the fire alarm control device controlling the action of the fire extinguisher; and provides a control method for the above-mentioned integrated energy storage system, including: controlling the coolant circulation unit and refrigerant circulation unit to automatically switch between cooling, heating and natural cooling modes according to the battery temperature and ambient temperature; wherein the following fire emergency steps are taken:

[0099] S100: Receives fire alarm action signals from the fire-fighting components for a level 3 fire alarm;

[0100] S200 sends a stop command to the PCS and starts a preset delay timer;

[0101] S300: Before the delay timer expires, the ECU sends a disconnection command to the DC circuit breaker in the high-voltage box of each battery cluster.

[0102] S400. After the delay timer expires, the BMS control power supply is cut off.

[0103] The beneficial effects of the above control method are as follows: The "low-high temperature dual-cycle + plate heat exchanger + distributed rooftop chiller" architecture enables stable operation of thermal management across multiple modes and a wide temperature range, greatly expanding the deployment area and adaptability of the energy storage system. Furthermore, a power-on delay time relay is used to control the tripping of the BMS power switch, ensuring a delay of several seconds after the fire alarm signal is issued before power is cut off. This ensures that before the final power cut-off, the ECU has sufficient time to reliably send a disconnect command to the DC circuit breaker in the high-voltage box via RS485 communication, prioritizing the disconnection of the high-voltage DC circuit and eliminating the risk of energized fire suppression.

[0104] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. An integrated energy storage system, comprising a container body, and further comprising battery modules, thermal management modules, electrical modules, string PCS modules, and step-up transformer modules integrated within the container body; the battery modules comprising multiple independent battery clusters, the multiple independent battery clusters forming at least two battery cluster sub-arrays in a string structure; characterized in that: The thermal management component includes a coolant circulation unit and a refrigerant circulation unit; the refrigerant circulation unit includes at least two distributed overhead chillers, each overhead chiller corresponding to one battery cluster subarray; the coolant circulation unit includes a low-temperature circulation loop and a high-temperature circulation loop, the low-temperature circulation loop including a liquid-cooled plate that cooperates with the heat exchange of the battery assembly and a low-temperature side-plate heat exchanger that cooperates with the heat exchange of the refrigerant circulation unit, the high-temperature circulation loop including a liquid-cooled plate that cooperates with the heat exchange of the battery assembly and a high-temperature side-plate heat exchanger that cooperates with the heat exchange of the refrigerant circulation unit; the string PCS component is configured with one string-type network PCS for each battery cluster.

2. The integrated energy storage system according to claim 1, characterized in that: The container body has a battery compartment, an electrical compartment, and a converter and booster compartment; the battery modules and thermal management components are located in the battery compartment, and each battery cluster subarray of the battery modules is located in one of the battery compartments; the electrical components are located in the electrical compartment; the string PCS modules and booster transformer modules are located in the converter and booster compartment, or the booster transformer modules are located in the converter and booster compartment, and the string PCS modules are located in the battery compartment.

3. The integrated energy storage system according to claim 1, characterized in that: Each of the above-mounted chillers has two independent chiller side plate heat exchangers, one of which is a refrigeration plate heat exchanger that exchanges heat with the low-temperature circulation loop, and the other is a heating plate heat exchanger that exchanges heat with the high-temperature circulation loop.

4. The integrated energy storage system according to claim 1, characterized in that: The low-temperature circulation loop and the high-temperature circulation loop are equipped with deionization devices and online conductivity detection sensors, which are respectively electrically connected to the electrical components.

5. The integrated energy storage system according to claim 1, characterized in that: The thermal management components also include a cabinet air conditioner located in the electrical compartment and an energy storage air conditioner located in the battery compartment.

6. The integrated energy storage system according to claim 1, characterized in that: The electrical components include a cabinet with a built-in main power distribution molded case circuit breaker, main power meter, and uninterruptible power supply, as well as an energy storage system ECU for performing DI signal acquisition, BMS management, thermal management monitoring, component monitoring, and human-machine interaction.

7. The integrated energy storage system according to claim 6, characterized in that: The integrated energy storage system also includes fire protection components integrated into the container, which include fire detectors, fire extinguishing devices, a data concentrator, and a fire alarm control device. The fire detectors include battery pack fire detectors and battery compartment fire detectors deployed in two stages. The fire extinguishing devices include battery compartment fire extinguishing agent nozzles, battery pack fire extinguishing agent nozzles, and a battery compartment water sprinkler system deployed in three stages. The data concentrator collects the detection signals from multiple fire detectors and transmits them to the fire alarm control device, which assesses the fire situation and controls the action of the fire extinguishers.

8. The integrated energy storage system according to claim 7, characterized in that: In the tripping electrical control circuit of the fire alarm control device that controls the action of the fire extinguisher, a power-delay time relay is provided. The power-delay time relay is used to control the tripping of the battery cluster BMS power switch, so that it performs the power cut-off after a delay of several seconds after the fire action signal is issued.

9. A control method for the integrated energy storage system according to claim 4, characterized in that, include: Based on the battery temperature and ambient temperature, the coolant circulation unit and refrigerant circulation unit are automatically switched between cooling, heating, and natural cooling modes. The deionization device is automatically or prompted to start / stop to purify the coolant online, based on the online conductivity monitoring value of the coolant circuit of the coolant circulation unit detected by the online conductivity detection sensor.

10. A control method for the integrated energy storage system according to claim 8, characterized in that, include: Based on the battery temperature and ambient temperature, the coolant circulation unit and refrigerant circulation unit are automatically switched between cooling, heating, and natural cooling modes; the following fire emergency procedures are implemented: S100: Receives fire alarm action signals from the fire-fighting components for a level 3 fire alarm; S200 sends a stop command to the PCS and starts a preset delay timer; S300: Before the delay timer expires, the ECU sends a disconnection command to the DC circuit breaker in the high-voltage box of each battery cluster. S400. After the delay timer expires, the BMS control power supply is cut off.

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