Dynamic reconfigurable battery system and interconnected energy storage converter bidirectional intelligent collaborative operation method

Abstract

The application discloses a dynamic reconfigurable battery system and an interconnected energy storage converter bidirectional intelligent collaborative operation method. For a coupled system of the dynamic reconfigurable battery system and the energy storage converter, the working state is refined and divided into six working conditions: "bidirectional optimization", "module optimization", "module optimization, power limit", "power optimization", "power optimization, module limit" and "bidirectional limit". Compared with a traditional control method in which the dynamic reconfigurable battery system and the energy storage converter are treated as two independent individuals, the application not only considers the working state of the dynamic reconfigurable battery system, calculates the output power range of the dynamic reconfigurable battery system according to the dynamic reconfigurable battery system topology, but also considers the actual power demand of the energy storage converter, and proposes corresponding dynamic reconfigurable battery system reconfiguration strategies and coupled system operation strategies for different working conditions. The dynamic reconfigurable battery system and the energy storage converter realize interactive regulation and coordinated operation, and the two parts of the coupled system are regarded as a whole.

Description

Technical Field

[0001] This invention belongs to the field of energy storage system operation control technology, specifically involving a bidirectional intelligent collaborative operation method between a dynamically reconfigurable battery system and an energy storage converter. Background Technology

[0002] In recent years, with the large-scale development and utilization of new energy sources and the development and construction of new power systems, energy storage technology has developed rapidly. Among them, battery energy storage technology has been widely used on the power supply side, grid side and load side due to its high flexibility and convenient installation.

[0003] The most prominent feature of a Dynamic Reconfigurable Battery System (DRBS) is that it can dynamically configure the battery topology in real time based on the current State of Charge (SOC) and State of Health (SOH) of the individual battery cells within the system, allowing for the addition or removal of some battery cells without affecting the charging and discharging process of other batteries.

[0004] However, most existing studies treat dynamically reconfigurable battery energy storage systems and power conversion systems (PCS) as two independent components, lacking integrated interaction strategies and bidirectional active control mechanisms. The operating state of the dynamically reconfigurable battery system does not take into account the operating state and power changes of the power conversion system. Conversely, the operating state and power changes of the power conversion system do not consider the current reconfiguration state of the dynamically reconfigurable battery system. Therefore, a smart and effective method for the intelligent collaborative operation of the reconfigurable battery system and the power conversion system is urgently needed to achieve information interaction and state inter-adjustment between the two.

[0005] A dynamically reconfigurable battery system based on energy information is a high-dimensional, dynamic, and complex system consisting of a massive number of differentiated battery cells and a massive number of power electronic switching devices, deeply coupled under different operating conditions. To fully leverage the inherent advantages of a dynamically reconfigurable battery system, the reconfiguration strategy design should consider both the SOC balancing of each battery module and the output or input power requirements of the energy storage converter, while ensuring the inherent safety of the system.

[0006] Under normal circumstances, while meeting operational safety boundaries, the maximum safe power output or input of the dynamically reconfigurable battery system after each topology reconfiguration must be greater than the required input or output power of the energy storage converter. However, in actual reconfiguration, due to numerous factors to consider, the output voltage, current, and power of the battery system after each reconfiguration may not meet the requirements of the PCS. In this case, the PCS and the dynamically reconfigurable battery system need to interact and mutually adjust within the allowable range of their respective operating states to always maintain the system in the optimal operating state and fully leverage the inherent advantages of the dynamically reconfigurable battery energy storage system. Summary of the Invention

[0007] To address the problems existing in the prior art, the present invention aims to provide a method for bidirectional intelligent cooperative operation of a dynamically reconfigurable battery system and an interconnected energy storage converter. This method simultaneously considers the output power range of the reconfigurable battery system and the power requirements of the energy storage converter, and accordingly reconfigures the DRBS topology or adjusts the PCS power command to achieve power balance between the two.

[0008] To achieve the above objectives, the technical solution adopted by this invention is as follows:

[0009] A bidirectional intelligent collaborative operation method for a dynamically reconfigurable battery system and an interconnected energy storage converter is proposed. This method considers the output voltage, current, and power electrical characteristics of the battery pack in the dynamically reconfigurable battery system. Combining the principles of "power matching" and "reasonable setting of the maintenance factor", the method completes information interaction and bidirectional intermodulation between the dynamically reconfigurable battery system and the energy storage converter in the coupled system (hereinafter referred to as the coupled system) to achieve the optimal operating state of the coupled system.

[0010] Includes the following steps:

[0011] S1: Based on the topology of the dynamically reconfigurable battery system, provide the electrical characteristics of the battery pack output voltage and current under the current state;

[0012] S2: Establish an information interaction mechanism between the dynamically reconfigurable battery system and the energy storage converter. Considering the two influencing factors of power supply and demand balance and reasonable selection of battery pack retention factor, the operating mode of the coupled system is classified into six operating conditions based on the current state of the dynamically reconfigurable battery system retention factor setting and the power demand of the energy storage converter. S3: Further analyze the operating mode of the coupled system under the six operating conditions, and propose appropriate system reconfiguration strategies for each of the six operating conditions. Clarify the energy flow mode of the coupled system, so that the coupled system truly becomes a dynamic whole and realizes the optimal operating mode after information interaction.

[0013] The specific method for step S1 is as follows:

[0014] Let B be the name of each battery module in a dynamically reconfigurable battery system. ij Its series switch is represented as S ij The bypass switch is represented as S. i Where i represents the row of the battery module and j represents the column of the battery module; M battery packs are connected in series to provide a higher terminal voltage, and N battery packs are connected in parallel to provide a larger terminal current; then the output voltage and current characteristics of the dynamically reconfigurable battery system are:

[0015]

[0016] In the formula: U dc U is a DC voltage. ij This indicates the battery module terminal voltage at the corresponding position in the corresponding row or column; g ij This indicates the switch status at the corresponding position in the corresponding row or column. g indicates the switch status when the module exits. ij =0, g when the module is put into operation ij =1; P is the output power of the dynamically reconfigurable battery system, I out This provides the output current for a dynamically reconfigurable battery system.

[0017] The specific method for step S2 is as follows:

[0018] S2.1: The main objects of the information interaction mechanism in the collaborative operation method are the output power range of the battery pack and the power demand of the energy storage converter; the purpose is to achieve power balance by completing the interaction between the dynamically reconfigurable battery system and the energy storage converter; the dynamically reconfigurable battery system changes the working state of the battery modules in the dynamically reconfigurable battery system by adjusting the holding factor α according to the actual situation, thereby changing the power output range of the dynamically reconfigurable battery system; the energy storage converter adjusts its own power demand after receiving different power commands.

[0019] S2.2: When selecting the retention factor α, the effects of the operating temperature, ambient humidity and initial state of charge of each battery module need to be considered. When the operating temperature is higher than 60℃, the self-discharge rate of the battery increases, which may accelerate the difference in the state of each battery in the battery pack. At this time, the retention factor needs to be balanced more frequently to maintain battery consistency in order to ensure the overall stability and efficiency of the dynamic reconfigurable battery system.

[0020] S2.3: Based on the current state of the dynamically reconfigurable battery system retention factor and the power demand of the energy storage converter, the system operation mode is divided into six types: "bidirectional optimal", "module optimal", "module optimal, power limited", "power optimal", "power optimal, module limited" and "bidirectional limited".

[0021] The specific method for step S3 is as follows:

[0022] S3.1: The "bidirectional optimal" operating condition means that neither the hold factor nor the power command of the energy storage converter needs to be adjusted. After setting the optimal hold factor, the output power range of the dynamically reconfigurable battery system is well matched with the power demand of the energy storage converter.

[0023] S3.2: The "module optimal" operating condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met. However, adjusting the energy storage converter scheduling command can make its power demand meet the output power of the dynamically reconfigurable battery system under the optimal holding factor state.

[0024] S3.3: The "Module Optimal, Power Limit" condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, even after adjusting the power demand of the energy storage converter to the limit, it still cannot match the output power of the dynamically reconfigurable battery system. In this case, the active power dispatch command of the energy storage converter should be adjusted according to the maximum output power of the dynamically reconfigurable battery system after the optimal holding factor is reconfigured.

[0025] If adjustments to the power requirements of the energy storage converter are necessary, the following principles should be followed:

[0026] Define the state variable for each battery module as follows:

[0027]

[0028] In the formula x ij The values ​​represent the working state of the battery module, i,j = 1, 2, 3, 4, 5, and are specifically taken as in equation (3).

[0029]

[0030] The active power reference value P of the energy storage converter ref Adjust according to the following formula

[0031]

[0032] In the formula, N' represents the number of battery modules actually put into operation after reconstruction, and SOC' represents the number of SOC modules. ave P' represents the average state of charge (SOC) of the current dynamically reconfigurable battery system, and P' represents the current active power dispatch command of the energy storage converter. ij This represents the state of charge of the battery module at the corresponding position in the i-th row and j-th column.

[0033] S3.4: The "power optimal" condition is when the power of the energy storage converter cannot be adjusted. After setting the optimal retention factor, the power demand of the energy storage converter cannot be met. At this time, the calculation and selection of the retention factor α should be reconsidered. The suboptimal retention factor α1 of the dynamic reconfigurable battery system should be calculated for this condition. After reconfiguration, the power demand of the energy storage converter can be met.

[0034] S3.5: "Optimal power, module limited" condition means that the power of the energy storage converter cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met. Even after adjusting the holding factor to the limit, the output power demand of the energy storage converter still cannot be met. In this case, the holding factor of the dynamically reconfigurable battery system should be readjusted according to the power demand of the energy storage converter.

[0035] S3.6: The "bidirectional limit" operating condition means that both the power demand of the energy storage converter and the holding factor of the dynamically reconfigurable battery system can be adjusted; after obtaining the reconfigurable topology of the dynamically reconfigurable battery system based on the current holding factor and calculating the output power of the dynamically reconfigurable battery system; considering the stability of the coupled system, the holding factor of the dynamically reconfigurable battery system and the power demand of the energy storage converter are adjusted according to the working priority of the dynamically reconfigurable battery system and the energy storage converter in the current state;

[0036] It should be noted that, considering the uncertainty of the system's working state, steps S3.1 to S3.6 are the overall operation methods under six parallel working conditions.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] 1. Based on the different connection methods of battery modules in a dynamically reconfigurable battery system, the output voltage and current characteristics of the dynamically reconfigurable battery system are clarified, and the output characteristics of the battery system are refined to the operating state of each battery module, making them accurate and clear.

[0039] 2. Establishing an information exchange mechanism between the dynamically reconfigurable battery system and the interconnected energy storage converter has the advantage of resolving the problem of unclear energy transfer boundaries between the battery system and the energy storage converter in the current coupled system. It considers the battery system's retention factor value and the power matching issue between the two, clarifies the operating status of the coupled system composed of the dynamically reconfigurable battery system and the interconnected energy storage converter, and provides clear guidance for relevant operation and maintenance personnel.

[0040] 3. For different operating states of the coupled system composed of a dynamically reconfigurable battery system and an energy storage converter, corresponding collaborative operation methods are proposed. The advantage is that it unifies the two parts of the coupled system into a unified whole, solving the problems of existing methods where the two parts of the coupled system lack information transmission, operate in isolation, and lack a clear operating mode, relying on experience to determine their respective operating states. It achieves the optimal operating mode of the coupled system after information interaction. Attached Figure Description

[0041] Figure 1 A diagram illustrating the overall steps of the intelligent collaborative operation method;

[0042] Figure 2 A matrix topology diagram of a dynamically reconfigurable battery system;

[0043] Figure 3 This is a topology diagram of a dynamically reconfigurable battery pack and energy storage converter interconnection system.

[0044] Figure 4 A schematic diagram illustrating the interactive coupling relationship between dynamic reconfiguration and the operating status of the energy storage converter;

[0045] Figure 5 A diagram illustrating the operating method of the system in a "bidirectional optimal" condition;

[0046] Figure 6 A diagram illustrating the operating method of the system in the "module optimal" condition;

[0047] Figure 7 A diagram illustrating the operating method of the system under the condition of "optimal module and limited power";

[0048] Figure 8 A diagram illustrating the operating method of the system in the "power-optimal" condition;

[0049] Figure 9 A diagram illustrating the operating method of the system under the condition of "optimal power and maximum module limit";

[0050] Figure 10 This is a diagram illustrating the operating method of the system under the "two-way limit" condition. Detailed Implementation

[0051] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0052] This invention discloses a bidirectional intelligent collaborative operation method for a dynamically reconfigurable battery system and an interconnected energy storage converter. First, based on the electrical characteristics of the dynamically reconfigurable battery system and the working principle of the energy storage converter, the cascade coupling interaction model between the two is studied. According to the power supply and demand relationship between the two and the principle that the selection of the holding factor should satisfy the system optimality, the operating states are divided into six types. Corresponding reconfiguration strategies and information interaction mechanisms are given for different operating states, the specific steps of which are as follows: Figure 1 .

[0053] The topology of a dynamically reconfigurable battery system is as follows: Figure 2 The dynamically reconfigurable battery system adopts a matrix M×N battery pack topology. Each battery module is represented as B. ij Its series switch is represented as S ij The bypass switch is represented as S. iHere, i represents the row where the battery module is located, and j represents the column where the battery module is located. M battery packs are connected in series to provide a higher terminal voltage, and N battery packs are connected in parallel to provide a larger terminal current. Each battery pack is equipped with a switch to connect or disconnect the battery pack, thereby controlling its charging or discharging. In addition, each parallel battery pack is equipped with a bypass switch, which closes when no parallel battery pack (row 1) is connected. In the actual topology, each switch is implemented using back-to-back MOSFETs to achieve independent battery module switching and control current flow, completely eliminating circulating current. Considering modular design and device current carrying capacity, each module is equipped with a set of bypass switches. The dynamically reconfigurable battery system provides DC input voltage to the energy storage converter, according to... Figure 1 The dynamically reconfigurable battery system topology shown can be used to obtain its voltage and current characteristics as follows:

[0054]

[0055] In the formula, U dc U is a DC voltage. ij This indicates the battery module terminal voltage at the corresponding position in the corresponding row or column; g ij This indicates the switch status at the corresponding position in the corresponding row or column. g indicates the switch status when the module exits. ij =0, g when the module is put into operation ij =1; P is the output power of the dynamically reconfigurable battery system, I out This provides the output current for a dynamically reconfigurable battery system.

[0056] In the design of dynamically reconfigurable battery systems, the retention factor is a key parameter that relates to how battery modules are optimally configured based on battery state and system requirements. However, the specific value of the retention factor is usually not fixed but determined based on factors such as the system's specific design goals, battery consistency, usage scenarios, and safety requirements. The calculation of the retention factor α considers the effects of each battery module's operating temperature, ambient humidity, and initial state of charge. At higher operating temperatures, the battery's self-discharge rate increases, potentially accelerating the differences in battery states within the battery pack. In this case, the retention factor may require more frequent equalization operations to maintain battery consistency and ensure the overall stability and efficiency of the system.

[0057] Figure 3 This diagram illustrates the energy storage converter topology connected to a dynamically reconfigurable battery pack and its PQ control mode. dc The input voltage is the DC side voltage, which is also the output voltage of the dynamically reconfigurable battery system. The midpoint voltages of the three-phase bridge arms of the converter are u... a u b u c The converter output uses an LC filter, Lv and C v These are the three-phase filter inductor and filter capacitor, respectively, r L This is the equivalent resistance of the filter inductor.

[0058] The interactive coupling relationship between dynamic reconfiguration and the operating state of the energy storage converter is illustrated as follows: Figure 4 As shown, for dynamically reconfigurable battery systems, factors to consider include the hold-up factor value, the operating boundaries of the dynamically reconfigurable battery system, and the range of its output power variation. For energy storage converters, grid dispatch requirements and their own safe operating boundary constraints must be considered. The coupling characteristics of the two systems are reflected in the fact that the actual output power of the dynamically reconfigurable battery system after reconfiguration will limit the active power output of the energy storage converter, and the grid-side power dispatch commands received by the energy storage converter will in turn affect the reconfiguration process of the dynamically reconfigurable system.

[0059] The reconfiguration flowchart of the dynamically reconfigurable battery system during the discharge phase and the coordinated operation and control strategy with the energy storage converter are detailed below.

[0060] During the discharge process, the minimum value of the retention factor α is taken as α. min =0.8, then we have

[0061] α min ≤α≤1 (2)

[0062] Assuming the active power of the energy storage converter PCS at the current operating state is P', the power command given by the dispatching instruction is P0, and the active power command value of the energy storage converter is P... ref .

[0063] The adjustable range of the energy storage converter power is set to be between 90% and 110% of the given dispatch command P0, which is the situation represented by equation (3).

[0064] 0.9P0≤P'≤1.1P0 (3)

[0065] Based on the principle of matching the output power range of the dynamically reconfigurable battery system with the power demand of the energy storage converter after receiving the dispatch command, and the reasonable selection of the retention factor of the dynamically reconfigurable battery system, and considering whether the retention factor after reconfiguration and the power demand of the energy storage converter can be readjusted, the coupled system operation states of the dynamically reconfigurable battery system and the energy storage converter are divided into 6 types. For each different operating condition, a reconfiguration strategy under the cooperative operation method is proposed.

[0066] ① "Two-way optimal" working condition

[0067] In the "bidirectional optimal" operating condition, neither the hold factor nor the power command of the energy storage converter needs adjustment. After setting the optimal hold factor, the dynamically reconfigurable battery system is reconfigured, and the output power range of the dynamically reconfigurable battery system is calculated after reconfiguration. At this point, the output power range of the dynamically reconfigurable battery system exactly matches the power demand of the energy storage converter, thus entering the "bidirectional optimal" operating condition. The corresponding cooperative operation method flowchart is as follows. Figure 5 As shown.

[0068] ② "Module Optimal" Operating Condition

[0069] The "module optimal" operating condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met. However, adjusting the energy storage converter scheduling command can make its power demand meet the output power of the dynamically reconfigurable battery system under the optimal holding factor state.

[0070] Based on the optimal retention factor α opt The output power range of the battery module is calculated using the corresponding system reconfiguration topology and compared with the power demand of the energy storage converter. If the power demand of the energy storage converter exceeds the current output power range of the dynamically reconfigurable battery system, then the optimal retention factor α should be maintained. opt Under the premise of [condition], the power output command of the energy storage converter is appropriately adjusted. If the power of the energy storage converter matches the dynamically reconfigurable battery system after adjustment, the system adopts a combined strategy of "optimal retention factor α" and "adjusting the power of the energy storage converter to match the battery pack" to complete system reconfiguration, which is called the "retention factor priority" principle. The corresponding collaborative operation method flowchart is as follows: Figure 6 As shown.

[0071] ③ "Optimal module, maximum power" operating condition

[0072] The "module optimal, power limited" operating condition means the hold factor cannot be adjusted. After setting the optimal hold factor, the output power range of the dynamically reconfigurable battery system cannot match the power demand of the energy storage converter. Even after adjusting the power command value of the energy storage converter to its limit, it still cannot match the output power of the dynamically reconfigurable battery system. In this case, the active power dispatch command of the energy storage converter should be adjusted according to the maximum output power of the dynamically reconfigurable battery system after reconfiguration with the optimal hold factor. The corresponding collaborative operation method flowchart is as follows. Figure 7 As shown.

[0073] When adjusting the power command of the energy storage converter, the following principles should be followed:

[0074] Define the state variable for each battery module as follows:

[0075]

[0076] In the formula xij The specific values ​​of the battery module's working state (i,j=1,2,3,4,5) are shown in equation (5).

[0077]

[0078] The active power reference value P of the energy storage converter ref You can refer to the following formula for adjustment.

[0079]

[0080] In the formula, N' represents the number of battery modules actually put into operation after reconstruction, and SOC' represents the number of SOC modules. ave P' represents the current average state of charge (SOC) of the dynamically reconfigurable battery system, and P' represents the current active power dispatch command of the energy storage converter. ij This represents the state of charge of the battery module at the corresponding position in row i and column j.

[0081] ④ "Optimal Power" Operating Condition

[0082] The "power optimal" operating condition is when the power of the energy storage converter cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met at this point, and the power command value of the energy storage converter cannot be further adjusted. The calculation and selection of the holding factor α should be reconsidered. The suboptimal holding factor α1 of the dynamically reconfigurable battery system is calculated. After reconfiguration, the output power of the dynamically reconfigurable battery system meets the power demand of the energy storage converter; this can also be called the "holding factor concession" principle. The corresponding collaborative operation method flowchart is as follows: Figure 8 As shown.

[0083] ⑤ "Optimal power, module limited" operating condition

[0084] The "optimal power, module limited" operating condition means the power of the energy storage converter cannot be adjusted. For this condition, an optimal hold factor α is set. opt Subsequently, the battery system and PCS power cannot be matched. At this point, the power command value of the energy storage converter cannot be adjusted, so readjustment and adjustment of the holding factor must be considered. If, after adjusting the holding factor to the critical limit, the output power range of the dynamically reconfigurable battery system still cannot match the output power of the dynamically reconfigurable battery system, the modules within the dynamically reconfigurable battery system should be reconfigured according to the active power dispatch command of the energy storage converter. The corresponding collaborative operation method flowchart is as follows. Figure 9 As shown.

[0085] ⑥ "Two-way limit" working condition

[0086] The "two-way fully limited" operating condition means that both the power demand of the energy storage converter and the holding factor of the dynamically reconfigurable battery system can be adjusted. After obtaining the reconfigurable topology of the dynamically reconfigurable battery system based on the current holding factor and calculating the output power of the dynamically reconfigurable battery system, considering the stable operation of the coupled system, the holding factor of the dynamically reconfigurable battery system and the power demand of the energy storage converter are adjusted according to the working priority of the dynamically reconfigurable battery system and the energy storage converter in the current state.

[0087] Assuming priority is given to ensuring the safe and stable operation of the dynamically reconfigurable battery system and its optimal topology, the holding factor is first adjusted. Then, based on the current holding factor, the topology of the dynamically reconfigurable battery system is obtained, and the output power range is calculated. The PCS active power command value is adjusted according to the obtained output power range to match the battery-side output power. The corresponding cooperative operation method flowchart is as follows: Figure 10 As shown.

[0088] The reconfiguration strategy of the dynamically reconfigurable battery system and the bidirectional intelligent collaborative operation method between the dynamically reconfigurable battery system and the energy storage converter can be summarized as follows: At the beginning of each reconfiguration cycle, the charge / discharge state, as well as the SOC (State of Charge) status and temperature of each row of battery modules, are detected first. Based on this information, the retention factor α corresponding to each row of the dynamically reconfigurable battery system is calculated, thus obtaining the optimal reconfiguration topology without considering the power requirements of the PCS. Based on the obtained reconfiguration topology, the range of voltage, current, and power that can be output can be calculated. The obtained voltage, current, and power are compared with the current requirements of the PCS. If the PCS requirements are met, the corresponding battery module is switched on and off according to the retention factor.

[0089] If the PCS operation requirements cannot be met at this time, adjustments need to be made according to the priority of influencing factors. First, the retention factor α needs to be recalculated based on the PCS operation requirements to make it the optimal retention factor that meets the PCS operation requirements. Then, it is determined whether the optimal retention factor meets the safe operating range of the dynamically reconfigurable battery system. If it meets the safe operating range, the dynamically reconfigurable battery system is reconfigured using this retention factor to meet the PCS operation requirements. If it does not meet the requirements, it needs to be reconfigured according to the current maximum permissible safe input or output power of the dynamically reconfigurable battery system.

[0090] This approach enables the PCS to guide the dynamically reconfigurable battery system to achieve optimal reconfiguration within the safe operating boundary. Furthermore, if the input or output power of the energy storage PCS can be adjusted within a certain range, the output power of the PCS can be adjusted according to the power range of the current optimal reconfigurable topology of the dynamically reconfigurable battery system to maintain the optimal operation of the dynamically reconfigurable battery energy storage system. This method allows the dynamically reconfigurable battery system to guide the PCS operation within the safe operating boundary.

Claims

1. A method for bidirectional intelligent collaborative operation of a dynamically reconfigurable battery system and an interconnected energy storage converter, characterized in that: Includes the following steps: S1: Based on the topology of the dynamically reconfigurable battery system, provide the electrical characteristics of the battery pack output voltage and current under the current state; S2: Establish an information interaction mechanism between the dynamic reconfigurable battery system and the energy storage converter. Considering the two influencing factors of power supply and demand balance and reasonable selection of battery pack retention factor, the operating mode of the coupled system is classified into six working conditions based on the current state of the dynamic reconfigurable battery system retention factor setting and the power demand of the energy storage converter. S3: Further analyze the operation mode of the coupled system under six working conditions, and propose appropriate system reconfiguration strategies for each of the six working conditions; clarify the energy flow mode of the coupled system, so that the coupled system truly becomes a dynamic whole and realizes the optimal operating mode after information interaction; The specific method for step S1 is as follows: S1.1: Let each battery module in the dynamically reconfigurable battery system be represented as B. ij Its series switch is represented as S ij The bypass switch is represented as S. i Where i represents the row of the battery module and j represents the column of the battery module; M battery packs are connected in series to provide a higher terminal voltage, and N battery packs are connected in parallel to provide a larger terminal current; then the output voltage and current characteristics of the dynamically reconfigurable battery system are: In the formula: U dc U is a DC voltage. ij This indicates the battery module terminal voltage at the corresponding position in the corresponding row or column; g ij This indicates the switch status at the corresponding position in the corresponding row or column. g indicates the switch status when the module exits. ij =0, g when the module is put into operation ij =1; P is the output power of the dynamically reconfigurable battery system, I out For the output current of a dynamically reconfigurable battery system; The specific method for step S2 is as follows: S2.1: The main objects of the information interaction mechanism in the collaborative operation method are the output power range of the battery pack and the power demand of the energy storage converter; the dynamic reconfigurable battery system changes the working state of the battery module in the dynamic reconfigurable battery system by adjusting the holding factor α according to the actual situation, thereby changing the power output range of the dynamic reconfigurable battery system; the energy storage converter adjusts its own power demand after receiving different power commands. S2.2: The selection of the retention factor α needs to consider the influence of three factors: the operating temperature of each battery module, the humidity of the operating environment, and the initial state of charge. S2.3: Based on the current state of the dynamically reconfigurable battery system retention factor and the power demand of the energy storage converter, the system operation mode is divided into six types: "bidirectional optimal", "module optimal", "module optimal, power limited", "power optimal", "power optimal, module limited" and "bidirectional limited".

2. The method for bidirectional intelligent collaborative operation of a dynamically reconfigurable battery system and an interconnected energy storage converter according to claim 1, characterized in that, The specific method for step S3 is as follows: S3.1: The "bidirectional optimal" operating condition means that neither the hold factor nor the power command of the energy storage converter needs to be adjusted. After setting the optimal hold factor, the output power range of the dynamically reconfigurable battery system is well matched with the power demand of the energy storage converter. S3.2: The "module optimal" operating condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met. However, adjusting the energy storage converter scheduling command can make its power demand meet the output power of the dynamically reconfigurable battery system under the optimal holding factor state. S3.3: "Module optimal, power limited" condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, even after adjusting the power demand of the energy storage converter to the limit, it still cannot match the output power of the dynamically reconfigurable battery system. In this case, the active power dispatch command of the energy storage converter should be adjusted according to the maximum output power of the dynamically reconfigurable battery system after the optimal holding factor is reconfigured. If adjustments to the power requirements of the energy storage converter are necessary, the following principles should be followed: Define the state variables of each battery module as follows: In the formula x ij The values ​​represent the working state of the battery module, i,j = 1, 2, 3, 4, 5, and are specifically taken as in equation (3). The active power reference value P of the energy storage converter ref Adjust according to the following formula In the formula, N' represents the number of battery modules actually put into operation after reconstruction, and SOC' represents the number of SOC modules. ave P' represents the average state of charge (SOC) of the current dynamically reconfigurable battery system, and P' represents the current active power dispatch command of the energy storage converter. ij This represents the state of charge of the battery module at the corresponding position in the i-th row and j-th column. S3.4: The "power optimal" operating condition is when the power of the energy storage converter cannot be adjusted. After setting the optimal retention factor, the power demand of the energy storage converter cannot be met. At this time, the calculation and selection of the retention factor α should be reconsidered. The suboptimal retention factor α1 of the dynamic reconfigurable battery system should be calculated for this operating condition. After reconfiguration, the power demand of the energy storage converter can be met. S3.5: "Optimal power, module limited" condition means that the power of the energy storage converter cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met. Even after adjusting the holding factor to the limit, the output power demand of the energy storage converter still cannot be met. In this case, the holding factor of the dynamically reconfigurable battery system should be readjusted according to the power demand of the energy storage converter. S3.6: The "bidirectional limit" operating condition means that both the power demand of the energy storage converter and the holding factor of the dynamically reconfigurable battery system can be adjusted; after obtaining the reconfigurable topology of the dynamically reconfigurable battery system based on the current holding factor and calculating the output power of the dynamically reconfigurable battery system; considering the stability of the coupled system, the holding factor of the dynamically reconfigurable battery system and the power demand of the energy storage converter are adjusted according to the working priority of the dynamically reconfigurable battery system and the energy storage converter in the current state; Steps S3.1 to S3.6 are the overall operation methods under six parallel working conditions.

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