Extensible industrial and commercial energy storage system

Abstract

The invention discloses an extensible industrial and commercial energy storage system which comprises an energy storage module, a battery management module, a liquid cooling circulation module, an energy management module and a fire protection module. The energy storage module is used for storing electric energy; the battery management module is used for collecting and uploading parameter information of the energy storage module; the liquid cooling circulation module is responsible for heat conversion of the storage module; the energy management module is used for charging and discharging management of the energy storage module; and the fire-fighting module is responsible for fire detection and fire extinguishing functions of the energy storage module. The requirement of a user for high-capacity energy storage can be met, meanwhile, cost and maintenance difficulty are reduced, and reliability and flexibility of the system are improved. By adopting the framework of unified management of multiple groups of battery clusters and the optimized energy management system and cooling system, the balanced output of the battery clusters can be realized, the service life of the battery is prolonged, and the energy storage efficiency is improved. The invention also has the advantages of easy integration and installation, low requirement on site space and the like, and is suitable for various industrial and commercial application environments.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and in particular to an expandable industrial and commercial energy storage system. Background Art

[0002] It was found in multiple projects that the existing industrial and commercial energy storage capacity is mainly 215kWh and 232kWh, which cannot meet the needs of some factories and mines. If multiple units are used, the cost is high. However, the battery compartment and converter equipment (PCS) of large energy storage systems are large in size. The failure of a single PCS causes the entire battery compartment to be shut down for maintenance, which has high maintenance costs. It also requires a dedicated cable channel, which is difficult to construct and has strict requirements on site space. It is not suitable for industrial and commercial environments. Some users have long-term plans and install in batches. The current industrial and commercial energy storage capacity expansion requires the addition of a complete energy storage system, which is relatively expensive. Summary of the invention

[0003] In order to solve the technical problems in the above background, the present invention provides a scalable industrial and commercial energy storage system, aiming to solve the deficiencies of existing industrial and commercial energy storage systems in terms of capacity, cost, maintenance, integration, etc., and provide a more efficient, reliable and flexible energy storage solution.

[0004] To achieve the above-mentioned purpose, the present invention provides an expandable industrial and commercial energy storage system, including: an energy storage module, a battery management module, a liquid cooling circulation module, an energy management module and a fire protection module;

[0005] The energy storage module is used to store electrical energy;

[0006] The battery management module is used to collect and upload parameter information of the energy storage module;

[0007] The liquid cooling circulation module is used for heat conversion of the storage module;

[0008] The energy management module is used for charging and discharging management of the energy storage module;

[0009] The fire protection module is used to be responsible for the fire detection and fire extinguishing functions of the energy storage module.

[0010] Preferably, the energy storage module includes several battery clusters, and the battery clusters include: 5 battery modules, a high-voltage junction box and a string converter; wherein each battery cluster can perform charging and discharging tasks independently.

[0011] Preferably, the battery management module includes: a collection unit and a transmission unit;

[0012] The acquisition unit is used to acquire parameter information of the energy storage module, and the parameter information includes: voltage, temperature and insulation resistance;

[0013] The transmission unit uploads the parameter information to the energy management module using a CAN / daisy chain serial communication method.

[0014] Preferably, the main circuit connection method of the expandable industrial and commercial energy storage system includes: the primary circuit is based on the string converter as the core, and after the energy management module receives the charging and discharging task, it is networked with the converter in a daisy chain manner via the RS485 bus, and the communication protocol adopts the standard Modbus communication protocol; each converter and the energy management module have a unique address; the converter actively sends data to the energy management module within the cycle time, and the energy management module sends a power instruction to the corresponding converter after calculation through the control strategy, and the DC side of the converter is connected to the battery cluster separately, and the AC side is connected in parallel, which is used for switching between simultaneous charging and discharging and separate charging and discharging.

[0015] Preferably, when the energy management module manages the discharge of the energy storage module, each battery cluster has a balanced output, so as to balance the electrical life of each battery cluster. The specific process includes: arbitrarily selecting the SOC difference between two battery clusters as an input variable, and when the difference is less than a preset value, selecting the battery cluster with a smaller SOC and the battery cluster with a larger SOC in each battery cluster by iteration, as shown in the following formula:

[0016] ΔSOC=SOC i -SOC i-1

[0017] In the formula, ΔSOC represents the difference in SOC of the battery cluster, SOC i and SOC i-1 Indicates the SOC value of two adjacent battery clusters;

[0018] Read the SOH data, find the best health state battery cluster and the worst health state battery cluster through iteration, and select the battery cluster with the largest SOH value and the largest SOC for discharge when:

[0019] 0≤P i，t <P max

[0020] Continue to open the corresponding clusters for discharge until:

[0021] P i，t ≥P max

[0022] Among them, P i，t is the accumulated power value of the discharged battery cluster, P max Calculate the target power value that needs to be charged or discharged for the system.

[0023] Preferably, in the system charging state: the energy management module randomly selects one or more battery clusters for charging according to the charging power, and the charging termination condition is:

[0024] SOC ≥ 100%

[0025] After the first selected battery cluster is fully charged and shut down, one or more battery clusters are randomly selected for charging until all battery clusters meet the charging termination condition.

[0026] Preferably, under the system discharge condition: the energy management module selects the priority discharge battery cluster number according to the discharge power size and the number of battery cluster charge and discharge cycle records, and the discharge termination condition is:

[0027] SOC≤1%

[0028] It is stipulated that 100 charge and discharge cycles are used as a node, and the battery life is kept constant by balancing the charge and discharge times of all battery clusters.

[0029] Preferably, during the operation of the system: if a single battery cluster has a communication failure or a power failure, it will shut down and prohibit charging and discharging, while other battery clusters will perform charging and discharging tasks normally; if a battery thermal runaway event occurs, it will be judged as a system failure, all battery clusters will stop charging and discharging, and the auxiliary power supply, air conditioning, dehumidifier, etc. will be cut off, and the fire protection module will intervene.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] With the development of industry and commerce, the demand for energy storage systems is increasing. The scalable industrial and commercial energy storage system of the present invention can meet the user's demand for high-capacity energy storage, while reducing costs and maintenance difficulties, and improving the reliability and flexibility of the system. By adopting an architecture for unified management of multiple battery clusters, as well as an optimized energy management system and cooling system, the invention can achieve balanced output of battery clusters, extend battery life, and improve energy storage efficiency. In addition, the system also has the advantages of easy integration and installation, and low site space requirements. It is suitable for various industrial and commercial application environments, provides users with stable power support, and promotes the application of renewable energy and efficient use of energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in 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 paying creative labor.

[0033] Figure 1 A schematic diagram of the system structure of an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the main circuit connection method of an embodiment of the present invention;

[0035] Figure 3 Schematic diagram of a battery cluster according to an embodiment of the present invention; wherein: Figure 3 (a) represents a top view; Figure 3 (b) represents the left view; Figure 3 (c) represents a side view; Figure 3 (d) represents the right side view;

[0036] Figure 4 Detailed structural diagram of the system of the embodiment of the present invention; wherein, Figure 4 (a) represents the appearance diagram; Figure 4 (b) represents the internal diagram;

[0037] Figure 5 A communication topology diagram of an embodiment of the present invention;

[0038] Figure 6 A schematic diagram of an energy management module according to an embodiment of the present invention;

[0039] Figure 7 Schematic diagram of the discharge process of an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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 are within the scope of protection of the present invention.

[0041] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] Embodiment 1

[0043] like Figure 1 As shown, it is a schematic diagram of the module structure of this embodiment, including: an energy storage module, a battery management module, a liquid cooling circulation module, an energy management module and a fire protection module; the energy storage module is used to store electric energy; the battery management module is used to collect and upload parameter information of the energy storage module; the liquid cooling circulation module is responsible for the heat conversion of the storage module; the energy management module is used for the charging and discharging management of the energy storage module; the fire protection module is responsible for the fire detection and fire extinguishing functions of the energy storage module.

[0044] The energy storage module includes several battery clusters, each of which includes five battery modules, a high-voltage combiner box and a string converter. Each battery cluster can independently perform charging and discharging tasks.

[0045] The battery management module includes: a collection unit and a transmission unit; the collection unit is used to collect parameter information of the energy storage module, and the parameter information includes: voltage, temperature and insulation resistance; the transmission unit uses CAN / daisy chain serial communication to upload the parameter information to the energy management module.

[0046] The following will describe in detail how the present invention solves the technical problems in practical work in conjunction with this embodiment.

[0047] (1) Battery module construction: First, connect five battery modules (PACK) to the high-voltage combiner box (GYX) and the string converter (PCS) to form a single battery cluster. Then, according to actual needs, configure N+1 battery clusters in the energy storage module. Figure 3 As shown, the battery grouping method is shown in Figure 1.

[0048] Table 1

[0049] Battery Cell Grouping method Voltage VDC CapacityAh Energy kWh Battery Cell 1 3.2 280 0.896 Battery Module 1P52S 166.4 280 46.592 Battery Cluster 1P260S 832 280 232.96 Battery System NP260S 832 280 N*232.96

[0050] (2) Module connection and debugging: The battery management module (BMS) is connected to each battery cluster through CAN / daisy chain serial communication to collect information such as the battery cluster’s voltage, temperature, insulation resistance, etc., and upload this information to the energy management module (EMS). At the same time, the liquid cooling circulation module, fire protection module, AC confluence device, power quality monitoring system, etc. are connected and debugged with the battery cluster and other components. After the connection is completed, the structure of the industrial and commercial energy storage system is as follows: Figure 4 shown.

[0051] like Figure 2 As shown, the main circuit connection mode of this embodiment is: the primary circuit is based on the string converter as the core. After receiving the charging and discharging task, the energy management module is connected to the converter in a daisy chain manner via the RS485 bus, and the communication protocol adopts the standard Modbus communication protocol; each converter and energy management module has a unique address; the converter actively sends data to the energy management module within the cycle time, and the energy management module sends a power instruction to the corresponding converter after calculating through the control strategy. The DC side of the converter is connected to the battery cluster separately, and the AC side is connected in parallel for switching between simultaneous charging and discharging and separate charging and discharging; the communication topology diagram of the system of this embodiment is shown in Figure 5 shown.

[0052] The specific process of the energy management module controlling the converter is as follows: the energy management module converts the data into a message in the Modbus protocol format through the protocol conversion module in the program for encapsulation. The message data has the address of the converter that needs to communicate and the CRC check code. After receiving the message, the controller of the converter performs a CRC check. If the data is correct, it can be used. If the CRC check code is wrong, it will be discarded. The battery cluster is connected separately on the DC side of the converter and connected in parallel on the AC side. The converter controller switches between simultaneous charging and discharging and separate charging and discharging according to the message instruction data received from the energy management module, and adjusts the charging and discharging power according to the power limit.

[0053] After the system is built, connected and debugged, the EMS is used to control the charging and discharging operations of the industrial and commercial energy storage system. The control process is as follows: Figure 6 As shown. Specifically, the control methods of "random repetition (the algorithm controls the time and size of output through learning, and the randomness and repetitiveness of the uncertain time and size can improve the safety and stability of the battery system), reciprocating (the algorithm controls the regular output of the battery cells through a certain time interval, sequence and mode), and reciprocating energy output (the algorithm controls the output of the battery in a reciprocating cycle in the order of the patrol to achieve an average output)" are adopted to make the N+1 battery clusters balanced in output and achieve the purpose of equalizing the battery life of each battery cluster. The control process is as follows:

[0054] The SOC difference between any two battery clusters is selected as the input variable. When the difference is less than the preset value, the battery clusters with smaller and larger SOCs in each battery cluster are selected iteratively, as shown in the following formula:

[0055] ΔSOC=SOC i -SOC i-1

[0056] In the formula, ΔSOC represents the difference in SOC of the battery cluster, SOC i and SOC i-1 Indicates the SOC value of two adjacent battery clusters;

[0057] Read the SOH (battery health status) data, find the best health status battery cluster and the worst health status battery cluster through iteration, and select the battery cluster with the largest SOH value and the largest SOC for discharge when:

[0058] 0≤P i，t <P max

[0059] Continue to open the corresponding clusters for discharge until:

[0060] P i，t ≥P max

[0061] Among them, P i，t is the accumulated power value of the discharged battery cluster, P max Calculate the target power value that needs to be charged or discharged for the system.

[0062] The charging and discharging process of the industrial and commercial energy storage system of this embodiment will be described in detail below.

[0063] Under charging conditions: When the battery is charging, the EMS randomly selects one or more battery clusters for charging according to the charging power (when the charging power is less than the rated power limit of a single cluster, it supports not allocating power to each cluster, directly comparing the SOC of each cluster, giving power to the cluster with the lowest SOC, and automatically switching to other clusters for charging after it is fully charged). The charging termination conditions are:

[0064] SOC ≥ 100%

[0065] After the first selected battery cluster is fully charged and shut down, one or more battery clusters are randomly selected for charging until all battery clusters meet the charging termination condition.

[0066] Under discharge conditions: EMS selects the priority discharge battery cluster number according to the discharge power and the number of charge and discharge cycles of the battery cluster (EMS compares the number of charge and discharge cycles recorded by the BMS of each cluster, and the lower number of cycles is discharged first. The cumulative number of every 100 charge and discharge cycles is the calibration node. The cumulative number that reaches 100 first will no longer be discharged. When the cumulative number of other clusters is calibrated to 100 times, the restriction is lifted). Discharge termination conditions:

[0067] SOC≤1%

[0068] It is stipulated that 100 charge and discharge cycles are used as a node, and the battery life is kept constant by balancing the charge and discharge times of all battery clusters. The discharge strategy formula is as follows:

[0069] ΔSOH=SOH i -SOH i-1

[0070] ΔSOC=SOC i -SOC i-1

[0071] In the formula, ΔSOC represents the difference in SOC of the battery cluster, SOC i and SOC i-1 Indicates the SOC value of two adjacent battery clusters; ΔSOH indicates the difference in SOH between battery clusters, SOH i and SOH i-1 Indicates the SOH value of two adjacent battery clusters.

[0072] The system iterates the optimal cluster according to the ΔSOH formula and gives priority to discharge. Then it iterates the cluster with the highest SOC according to the ΔSOC formula and gives priority to discharge. Determine the number of discharges in this round and finally select the cluster to be discharged. Select the corresponding number of clusters according to the power target value to be discharged and start discharge. The process is as follows: Figure 7 shown.

[0073] Embodiment 2

[0074] The specific information of each key component of the system of the present invention will be described in detail below in conjunction with this embodiment.

[0075] (1) Battery Module (PACK): A battery module is a collection of multiple battery cells for storing electrical energy. In the present invention, the battery module adopts advanced battery technology and has high energy density, long cycle life and good safety. For example, a lithium-ion battery module is used, which has a high energy density and can meet the large capacity requirements of industrial and commercial energy storage modules.

[0076] (2) PCS: PCS is a key device for realizing power conversion. It can convert the DC power of the battery pack into AC power, or convert AC power into DC power. The present invention adopts a design in which each battery cluster corresponds to a small PCS. Compared with the traditional large PCS, it has the advantages of small size, easy integration and installation, and low maintenance cost. At the same time, PCS also has high power conversion efficiency and stable performance, which can ensure the reliable operation of the overall industrial and commercial energy storage system.

[0077] (3) Energy Management Module (EMS): EMS is the brain of the overall industrial and commercial energy storage system, responsible for managing and controlling the charging and discharging of battery clusters. It adopts the control method of "random repetition, cyclic reciprocating, and round-robin energy output", which can make the N+1 battery clusters output balanced and achieve the purpose of equalizing the battery life of each battery cluster. For example, when charging, EMS intelligently selects the battery cluster to be charged based on the charging power and the SOC of each battery cluster, avoiding the situation where some battery clusters are overcharged and other battery clusters are undercharged. When discharging, EMS gives priority to discharging battery clusters with lower cycle times based on the discharge power and the number of battery cluster charge and discharge cycles, achieving a balanced charge and discharge number of battery clusters and extending the battery life.

[0078] (4) Liquid cooling circulation module: The liquid cooling circulation module consists of a large chiller and pipelines, which are responsible for cooling the battery cluster to keep the battery temperature within an appropriate range. The module removes the heat generated by the battery cluster by circulating the coolant in the pipeline, thereby improving the performance and life of the battery. For example, the use of efficient coolant and optimized pipeline layout can ensure the uniformity and stability of the cooling effect.

[0079] (5) Firefighting module: The firefighting module includes fire detectors and fire extinguishing devices, which are used to monitor and deal with fire hazards in battery clusters. When the fire detector detects signs of fire, the fire extinguishing device will automatically start to quickly extinguish the flames and protect the safety of industrial and commercial energy storage systems. For example, using smoke detectors and perfluorohexane fire extinguishing devices can detect fires in time and extinguish them effectively.

[0080] The embodiments described above are only descriptions of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A scalable industrial and commercial energy storage system, characterized in that: include: Energy storage module, battery management module, liquid cooling circulation module, energy management module and fire protection module; The energy storage module is used to store electrical energy; The battery management module is used to collect and upload parameter information of the energy storage module; The liquid cooling circulation module is used for heat conversion of the storage module; The energy management module is used for charging and discharging management of the energy storage module; The fire protection module is used to be responsible for the fire detection and fire extinguishing functions of the energy storage module.

2. The expandable industrial and commercial energy storage system according to claim 1, characterized in that: The energy storage module includes several battery clusters, each of which includes five battery modules, a high-voltage junction box and a string converter; each battery cluster can independently perform charging and discharging tasks.

3. The expandable industrial and commercial energy storage system according to claim 1, characterized in that: The battery management module includes: a collection unit and a transmission unit; The acquisition unit is used to acquire parameter information of the energy storage module, and the parameter information includes: voltage, temperature and insulation resistance; The transmission unit uploads the parameter information to the energy management module using a CAN / daisy chain serial communication method.

4. The expandable industrial and commercial energy storage system according to claim 1, characterized in that: The main circuit connection method of the expandable industrial and commercial energy storage system includes: the primary circuit is based on the string converter as the core, and after the energy management module receives the charging and discharging task, it is networked with the converter in a daisy chain manner via the RS485 bus, and the communication protocol adopts the standard Modbus communication protocol; each converter and the energy management module have a unique address; the converter actively sends data to the energy management module within the cycle time, and the energy management module sends a power instruction to the corresponding converter after calculation through the control strategy, and the DC side of the converter is connected to the battery cluster separately, and the AC side is connected in parallel, which is used for switching between simultaneous charging and discharging and separate charging and discharging.

5. The expandable industrial and commercial energy storage system according to claim 2, characterized in that: When the energy management module manages the discharge of the energy storage module, the output of each battery cluster is balanced to balance the electrical life of each battery cluster. The specific process includes: arbitrarily selecting the SOC difference between two battery clusters as an input variable, and when the difference is less than a preset value, selecting the battery cluster with a smaller SOC and the battery cluster with a larger SOC in each battery cluster by iteration, as shown in the following formula: ΔSOC=SOC i -SOC i-1 In the formula, ΔSOC represents the difference in SOC of the battery cluster, SOC i and SOC i-1 Indicates the SOC value of two adjacent battery clusters; Read the SOH data, find the best health state battery cluster and the worst health state battery cluster through iteration, and select the battery cluster with the largest SOH value and the largest SOC for discharge when: 0≤P i，t <P max Continue to open the corresponding clusters for discharge until: P i，t ≥P max Among them, P i，t is the accumulated power value of the discharged battery cluster, P max Calculate the target power value that needs to be charged or discharged for the system.

6. The expandable industrial and commercial energy storage system according to claim 2, characterized in that: In the system charging state: the energy management module randomly selects one or more battery clusters for charging according to the charging power, and the charging termination condition is: SOC ≥ 100% After the first selected battery cluster is fully charged and shut down, one or more battery clusters are randomly selected for charging until all battery clusters meet the charging termination condition.

7. The expandable industrial and commercial energy storage system according to claim 2, characterized in that: Under the system discharge condition: the energy management module selects the priority discharge battery cluster number according to the discharge power and the number of battery cluster charge and discharge cycles. The discharge termination condition is: SOC≤1% It is stipulated that 100 charge and discharge cycles are used as a node, and the battery life is kept constant by balancing the charge and discharge times of all battery clusters.

8. The expandable industrial and commercial energy storage system according to claim 2, characterized in that: During system operation: if a single battery cluster has a communication failure or a power failure, it will shut down and prohibit charging and discharging, while other battery clusters will perform charging and discharging tasks normally; if a battery thermal runaway event occurs, it will be judged as a system failure, all battery clusters will stop charging and discharging, and the auxiliary power supply, air conditioning, dehumidifier, etc. will be cut off, and the fire protection module will intervene.

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