Bidirectional intelligent cooperative operation method for dynamic reconfigurable battery system and interconnected energy storage converter

Abstract

The invention discloses a bidirectional intelligent cooperative operation method for a dynamic reconfigurable battery system and an interconnected energy storage converter, and aims at a coupling system for the operation of the dynamic reconfigurable battery system and the energy storage converter to refine the working state of the coupling system. The method is divided into six working conditions: 'two-way optimal ', 'module optimal', 'module optimal ', power limit entering', 'power optimal ', 'power optimal', module limit entering 'and'two-way limit entering'. Compared with a traditional control method in which the dynamic reconfigurable battery system and the energy storage converter are treated as two independent operating individuals, the method has the advantages that the working state of the dynamic reconfigurable battery system is considered, and the output power range of the dynamic reconfigurable battery system is calculated according to the topological structure of the dynamic reconfigurable battery system; meanwhile, the actual power requirement of the energy storage converter is considered, and corresponding dynamic reconfigurable battery system reconfiguration strategies and coupling system operation strategies are provided according to different working states. The dynamic reconfigurable battery system and the energy storage converter realize interactive regulation and coordinated operation, and the two parts of the coupling system are regarded as a whole.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage system operation control, and specifically relates to a bidirectional intelligent collaborative operation method between a dynamically reconfigurable battery system and an energy storage converter. Background Art

[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 easy installation.

[0003] The most prominent feature of the 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 health (SOH) of the battery cells inside the system, and can put some battery cells into or out without affecting the charging and discharging process of other batteries.

[0004] However, most existing studies regard the dynamic reconfigurable battery energy storage system and the energy storage converter (Power Conversion System, PCS) as two independent parts, and an integrated interaction strategy and a two-way active control mechanism are still lacking. The working state of the dynamic reconfigurable battery system does not take into account the operating state and power changes of the energy storage converter. The operating state and power changes of the energy storage converter also do not take into account the current reconstruction state of the dynamic reconfigurable battery system. Therefore, there is an urgent need for an intelligent and effective method for the intelligent coordinated operation of the reconfigurable battery system and the energy storage converter to achieve information interaction and state mutual adjustment between the two.

[0005] The dynamic reconfigurable battery system based on energy informatization is a high-dimensional dynamic complex system formed by the deep coupling of a large number of differentiated battery bodies and a large number of power electronic power switching devices under different operating conditions. In order to give full play to the essential advantages of the dynamic reconfigurable battery system, the reconstruction strategy design of the dynamic reconfigurable battery system should consider the SOC balance of each battery module on the basis of achieving the intrinsic safety of the system, and also consider the output or input power requirements of the energy storage converter.

[0006] Under normal circumstances, on the basis of meeting the operational safety boundary, after each topology reconstruction, the maximum safe power that the dynamically reconfigurable battery system can output or input needs to be greater than the power that the energy storage converter needs to input or output. However, in actual reconstruction, due to the need to consider many factors, the output voltage, current, and power of the battery system after each reconstruction may not meet the needs of the PCS. At this time, the PCS needs to exchange information with the dynamically reconfigurable battery system, and bidirectionally adjust within the allowable range of the operating status of the two to always keep the system in the optimal achievable operating state and give full play to the essential advantages of the dynamically reconfigurable battery energy storage system. Summary of the invention

[0007] In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a method for bidirectional intelligent collaborative operation of a dynamically reconfigurable battery system and an interconnected energy storage converter. The output power range of the reconfigurable battery system and the power demand of the energy storage converter are considered at the same time, and the topology of the DRBS is reconstructed or the PCS power instruction is adjusted accordingly to achieve power balance between the two.

[0008] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0009] A method for bidirectional intelligent cooperative operation of a dynamic reconfigurable battery system and an interconnected energy storage converter, taking into account the output voltage, current, and power electrical quantity characteristics of the battery pack in the dynamic reconfigurable battery system, combining the "power matching" principle and the "reasonable setting of the maintenance factor" principle, in a coupling system in which the dynamic reconfigurable battery system and the energy storage converter are operated, hereinafter referred to as the coupling system, to complete the information interaction and bidirectional intermodulation between the dynamic reconfigurable battery system and the energy storage converter, so as to achieve the optimal operation state of the coupling system;

[0010] The following steps are involved:

[0011] S1: According to the topological structure of the dynamically reconfigurable battery system, the electrical quantity characteristics of the output voltage and current of the battery pack in the current state are given;

[0012] S2: Establish an information interaction mechanism between the dynamic reconfigurable battery system and the energy storage inverter, consider the two influencing factors of power supply and demand balance and reasonable selection of battery pack retention factor, and classify the operation mode of the coupling system into six working conditions according to the current state of the dynamic reconfigurable battery system retention factor setting and the power demand of the energy storage inverter; S3: Further analyze the operation mode of the coupling system under the six working conditions, and propose appropriate system reconstruction strategies for the six working conditions; clarify the energy flow pattern of the coupling system, so that the coupling system truly becomes a dynamic whole, and realizes the optimal operation mode after information interaction.

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

[0014] Assume that each battery module in the dynamically reconfigurable battery system is represented by B ij , whose series switch is represented by S ij , the bypass switch is represented by S i ; where i represents the row where the battery module is located, and j represents the column where the battery module is located; where 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; the output voltage and current characteristics of the dynamically reconfigurable battery system are:

[0015]

[0016] Where: U dc is the DC voltage, U ij Indicates the battery module terminal voltage at the corresponding position of the corresponding row or column; g ij Indicates the switch status of the corresponding row or column. When the module exits, g ij =0, when the module is put into use g ij =1; P is the output power of the dynamically reconfigurable battery system, I out Output current for dynamically reconfigurable battery systems.

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

[0018] S2.1: It is clear that 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 complete the interaction between the dynamic reconfigurable battery system and the energy storage converter to achieve power balance; the dynamic reconfigurable battery system can change the working state of the battery module in the dynamic reconfigurable battery system by adjusting the retention factor α according to the actual situation, thereby changing the power output range of the dynamic reconfigurable battery system; after receiving different power instructions, the energy storage converter adjusts its own power demand;

[0019] S2.2: For the selection of the retention factor α, it is necessary to consider the operating temperature, working environment humidity and initial charge state of each battery module; when the operating temperature is higher than 60°C, the self-discharge rate of the battery increases, which may lead to the acceleration of the difference in the state of each battery in the battery pack. At this time, the retention factor requires more frequent balancing operations to maintain battery consistency, so as to ensure the overall stability and efficiency of the dynamically reconfigurable battery system;

[0020] S2.3: According to the dynamic reconfigurable battery system retention factor and the energy storage inverter power demand in the current state, the system operation modes are divided into six types: "bidirectional optimal", "module optimal", "module optimal, power limit", "power optimal", "power optimal, module limit" and "bidirectional limit".

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

[0022] S3.1: The “bidirectional optimal” operating condition is that the holding factor and the energy storage converter power command do not need to be adjusted. After setting the optimal holding 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” working condition is that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met, but adjusting the energy storage converter scheduling instruction 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 is optimal, power is limited" working condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter is adjusted to the limit, but it still cannot match the output power of the dynamic reconfigurable battery system. In this case, the active power dispatch instruction of the energy storage converter should be adjusted according to the maximum output power of the dynamic reconfigurable battery system after reconstruction with the optimal holding factor.

[0025] If you need to adjust the power demand of the energy storage converter, refer to the following principles:

[0026] Define the state variables of each battery module as

[0027]

[0028] Where x ij Indicates the working state of the battery module, i,j = 1, 2, 3, 4, 5, and the specific value is as shown in formula (3)

[0029]

[0030] Then the active power reference value P of the energy storage converter is ref Refer to the following formula for adjustment

[0031]

[0032] Where N' is the number of battery modules actually put into operation after reconstruction, SOC' ave is the average value of the state of charge (SOC) of the current dynamically reconfigurable battery system, P' is the current active power dispatch instruction of the energy storage converter; SOC ij is the state of charge of the battery module at the corresponding position of the i-th row and the j-th column;

[0033] S3.4: The "power optimal" working condition is 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. At this time, the calculation and selection of the holding factor α should be considered again; the suboptimal holding factor α1 of the dynamically reconfigurable battery system should be calculated for this working condition, and the power demand of the energy storage converter should be met after reconfiguration;

[0034] S3.5: The "power is optimal, the module is limited" working condition is 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. After the holding factor is adjusted to the limit, it still cannot meet the output power demand of the energy storage converter. In this case, the holding factor of the dynamically reconfigurable battery system should be re-set according to the power demand of the energy storage converter;

[0035] S3.6: The "bidirectional limit" working condition means that the power demand of the energy storage converter and the dynamic reconfigurable battery system retention factor can be adjusted; the dynamic reconfigurable battery system reconstruction topology is obtained according to the current retention factor, and the output power of the dynamic reconfigurable battery system is calculated; considering the stability of the coupled system, according to the working priorities of the dynamic reconfigurable battery system and the energy storage converter in the current state, the dynamic reconfigurable battery system retention factor and the energy storage converter power demand are adjusted respectively;

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

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

[0038] 1. According to the different connection methods of battery modules in the 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 status of each battery module, which is accurate and clear.

[0039] 2. Establish an information interaction mechanism between the dynamic reconfigurable battery system and the interconnected energy storage inverter. The advantage is that it solves the problem of unclear energy transfer boundaries between the battery system and the energy storage inverter in the coupling system in the current mode. Consider the value of the battery system retention factor and the power matching problem of both parties, clarify the working state of the coupling system composed of the dynamic reconfigurable battery system and the interconnected energy storage inverter, and provide clear guidance for the operation of relevant operation and maintenance specialists.

[0040] 3. According to the different working states of the coupling system composed of the dynamic reconfigurable battery system and the energy storage converter, the corresponding collaborative operation methods are given respectively. The advantage is that the two parts of the coupling system become a unified whole, solving the problem that there is no information transmission between the two parts of the coupling system in the existing method, each operates in isolation, the system lacks a clear operating mode, and each working state is set based on experience. The optimal operation mode of the coupling system after information interaction is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The diagram is a general step-by-step description of the intelligent collaborative operation method;

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

[0043] Figure 3 It is the topology diagram of the interconnection system of the dynamic reconfigurable battery pack and the energy storage converter;

[0044] Figure 4 It is a schematic diagram of the interactive coupling relationship between dynamic reconstruction and the operating state of the energy storage converter;

[0045] Figure 5 This is the operating method diagram of the system in the "two-way optimal" working condition;

[0046] Figure 6 This is a diagram of the system's operating method when it is in the "module optimal" condition;

[0047] Figure 7 This is a diagram of the system's operation method when it is in the "module optimal, power limited" condition;

[0048] Figure 8 This is a diagram of the operation method when the system is in the "optimal power" condition;

[0049] Fig. 9 This is a diagram of the system's operation method when it is in the "optimal power, module limit" condition;

[0050] Fig.10 This is a diagram of the system's operating method when it is in the "two-way limit" condition. DETAILED DESCRIPTION

[0051] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] The present invention discloses a method for bidirectional intelligent collaborative operation of a dynamic reconfigurable battery system and an interconnected energy storage converter. First, based on the electrical quantity characteristics of the dynamic 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 selection of the retention factor, the operating state is divided into six types to meet the system optimal principle. Corresponding reconstruction strategies and information interaction mechanisms are given for different working states. The specific steps are as follows: Figure 1 .

[0053] The topology of the 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 , whose series switch is represented by S ij , the bypass switch is represented by S i. Among them, i represents the row where the battery module is located, and j represents the column where the battery module is located. Among them, 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 configured with a switch to connect or disconnect the battery pack to control its charging or discharging. In addition, each parallel battery pack is configured with a bypass switch. When a parallel battery pack (1 row) is not connected, the bypass switch is closed. In the actual topology, each switch is implemented with back-to-back MOSFETs to achieve independent switching of battery modules, control the current flow direction, and completely eliminate circulating current. At the same time, considering the modular design and device current carrying capacity, each module is equipped with a set of bypass switches. The dynamically reconfigurable battery system provides a DC input voltage for the energy storage inverter. Figure 1 The dynamically reconfigurable battery system topology shown in the figure shows that its voltage and current characteristics are:

[0054]

[0055] Where U dc is the DC voltage, U ij Indicates the battery module terminal voltage at the corresponding position of the corresponding row or column; g ij Indicates the switch status of the corresponding row or column. When the module exits, g ij =0, when the module is put into use g ij =1; P is the output power of the dynamically reconfigurable battery system, I out Output current for dynamically reconfigurable battery systems.

[0056] In the design of dynamically reconfigurable battery systems, the retention factor is a key parameter, which involves how to optimize the configuration between battery modules according to the battery status and system requirements. However, the specific value of the retention factor is usually not fixed, but is determined based on factors such as the specific design goals of the system, battery consistency, usage scenarios, and safety requirements. For the calculation of the retention factor α, the three effects of the operating temperature, working environment humidity, and initial state of charge of each battery module are considered. At higher operating temperatures, the self-discharge rate of the battery increases, which may lead to accelerated differences in the states of each battery in the battery pack. At this time, the retention factor may require more frequent balancing operations to maintain battery consistency to ensure the overall stability and efficiency of the system.

[0057] Figure 3 The topology of the energy storage converter connected to the dynamically reconfigurable battery pack and the schematic diagram of the PQ control mode. dc is the DC side input voltage, that is, 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 They are three-phase filter inductors and filter capacitors, r L is the equivalent resistance of the filter inductor.

[0058] The interactive coupling relationship between dynamic reconstruction and the operating state of the energy storage converter is shown in the figure below: Figure 4 As shown in the figure, for the dynamically reconfigurable battery system, the factors that need to be considered include the value of the retention factor, the operating boundary of the dynamically reconfigurable battery system, and the range of its output power; for the energy storage converter, the grid dispatching requirements and its own safe operating boundary constraints must be considered. The system coupling characteristics formed by the two are reflected in the fact that the actual output power of the dynamically reconfigurable battery system after reconstruction will limit the active power output of the energy storage converter, and the grid-side power dispatching instructions received by the energy storage converter will react to the reconstruction process of the dynamically reconfigurable system.

[0059] The reconstruction flow chart of the dynamic reconfigurable battery system during the discharge phase and the coordinated operation and control strategy with the energy storage inverter are detailed as follows.

[0060] During the discharge process, the minimum limit of the holding factor α is α min =0.8, then we have

[0061] α min ≤α≤1 (2)

[0062] Assume that the active power of the energy storage converter PCS at the current operating state is P', the power command value given by the dispatch 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 90% to 110% of the given dispatch instruction P0, which is the situation expressed by formula (3):

[0064] 0.9P0≤P'≤1.1P0 (3)

[0065] According to the matching of the output power range of the dynamic reconfigurable battery system with the power demand of the energy storage converter after receiving the dispatching instruction and the reasonable principle of selecting the dynamic reconfigurable battery system retention factor, the coupling system operation states of the dynamic reconfigurable battery system and the energy storage converter are divided into 6 types according to whether the retention factor after reconstruction and the power demand of the energy storage converter can be adjusted again, and the reconstruction strategies under the collaborative operation method are proposed for different working conditions.

[0066] ① “Bidirectional optimal” working condition

[0067] The "two-way optimal" working condition is that the holding factor and the energy storage converter power command do not need to be adjusted. After setting the optimal holding factor, the dynamically reconfigurable battery system is reconfigured, and the output power range of the dynamically reconfigurable battery system is calculated after reconstruction. At this time, the output power range of the dynamically reconfigurable battery system just matches the power demand of the energy storage converter, entering the "two-way optimal" working condition. The corresponding collaborative operation method flow chart is as follows Figure 5 shown.

[0068] ② “Module Optimal” Working Condition

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

[0070] According to the optimal retention factor α opt The corresponding system reconstruction topology is calculated to obtain the battery module output power range and compared with the energy storage inverter power demand. If the power demand of the energy storage inverter exceeds the current output power range of the dynamically reconfigurable battery system, the optimal holding factor α should be guaranteed. opt Under the premise of , 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 the combination strategy of "optimal retention factor α" and "adjusting the power of the energy storage converter to match the battery pack" to complete the system reconstruction, which is called the "retention factor priority" principle. The corresponding collaborative operation method flow chart is as follows Figure 6 shown.

[0071] ③ "Optimal module, power limit" working condition

[0072] The "module is optimal, power is limited" working condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, the output power range of the dynamic reconfigurable battery system cannot match the power demand of the energy storage inverter. After adjusting the power command value of the energy storage inverter to the limit, it still cannot match the output power of the dynamic reconfigurable battery system. In this case, the active power dispatching command of the energy storage inverter should be adjusted according to the maximum output power of the dynamic reconfigurable battery system after reconstruction with the optimal holding factor. The corresponding collaborative operation method flow chart is as follows: Figure 7 shown.

[0073] When adjusting the power command of the energy storage converter, refer to the following principles:

[0074] Define the state variables of each battery module as

[0075]

[0076] Where xij Indicates the working state of the battery module (i, j = 1, 2, 3, 4, 5). The specific value is as shown in formula (5):

[0077]

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

[0079]

[0080] Where N' is the number of battery modules actually put into operation after reconstruction, SOC' ave is the average state of charge of the current dynamically reconfigurable battery system, P' is the current active power dispatch instruction of the energy storage converter; SOC ij It is the charge state of the battery module at the corresponding position of the i-th row and the j-th column.

[0081] ④ “Optimal power” working condition

[0082] The "power optimal" working condition is that the power of the energy storage inverter cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage inverter cannot be met. At this time, the power command value of the energy storage inverter cannot be adjusted further. The calculation and selection of the holding factor α should be considered again. The suboptimal holding factor α1 of the dynamically reconfigurable battery system is calculated. After reconstruction again, the output power of the dynamically reconfigurable battery system meets the power demand of the energy storage inverter, which can also be called the "holding factor concession" principle. The corresponding collaborative operation method flow chart is as follows: Figure 8 shown.

[0083] ⑤ "Optimal power, module limit" working condition

[0084] The "power is optimal, module is limited" working condition is that the power of the energy storage converter cannot be adjusted. For this working condition, the optimal holding factor α is set. opt After that, the battery system and PCS power cannot match. At this time, the power command value of the energy storage converter cannot be adjusted, so it is necessary to consider resetting and adjusting the holding factor. If the output power range of the dynamically reconfigurable battery system still cannot match the output power of the dynamically reconfigurable battery system after the holding factor is adjusted to the critical limit, the module inside the dynamically reconfigurable battery system should be reconstructed according to the active power dispatching command of the energy storage converter. The corresponding collaborative operation method flow chart is as follows: Fig. 9 shown.

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

[0086] The "bidirectional limit" working condition means that both the power demand of the energy storage inverter and the holding factor of the dynamic reconfigurable battery system can be adjusted; the reconstruction topology of the dynamic reconfigurable battery system is obtained according to the current holding factor, and the output power of the dynamic reconfigurable battery system is calculated; considering the stable operation of the coupled system, the holding factor of the dynamic reconfigurable battery system and the power demand of the energy storage inverter are adjusted according to the working priorities of the dynamic reconfigurable battery system and the energy storage inverter in the current state.

[0087] Assume that priority is given to ensuring the safe and stable operation of the dynamically reconfigurable battery system and the optimal topology of the system. The retention factor is adjusted first, and then the topology of the dynamically reconfigurable battery system is obtained according to the current retention factor, and the output power range is calculated. According to the obtained output power range, the PCS active power command value is adjusted to match the output power of the battery side. The corresponding collaborative operation method flow chart is as follows: Fig.10 shown.

[0088] The overall description of the reconstruction strategy of the dynamic reconfigurable battery system and the bidirectional intelligent collaborative operation method of the dynamic reconfigurable battery system and the energy storage converter can be summarized as follows: at the beginning of each reconstruction cycle, the charge and discharge state, the SOC (state of charge) state, temperature and other information of each row of battery modules are first detected, and the retention factor α corresponding to each row of the current dynamic reconfigurable battery system is calculated based on this information, and the optimal reconstruction topology without considering the power demand of the PCS can be obtained. Based on the obtained reconstruction topology, the current output voltage, current and power range can be calculated. The obtained voltage, current and power are compared with the current required information of the PCS. If the PCS requirements can be met, the corresponding battery modules are switched 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 the influencing factors. First, the retention factor α needs to be recalculated according to the PCS operation requirements so that the factor is the optimal retention factor when the PCS operation requirements are met. Then, it is determined whether the optimal retention factor meets the safe operating range of the dynamically reconfigurable battery system. If the safe operating range is met, the dynamically reconfigurable battery system is reconfigured with this retention factor to meet the PCS operation requirements. If not, it needs to be reconfigured according to the current maximum allowable dynamic reconfigurable battery system safe input or output power.

[0090] In this way, the PCS guides the dynamic reconfigurable battery system to achieve optimal reconstruction within the safe operation boundary. In addition, if the input or output power of the energy storage PCS can be adjusted within a certain range, the PCS output power can be adjusted according to the power range of the optimal reconstruction topology of the current dynamic reconfigurable battery system to maintain the optimal operation of the dynamic reconfigurable battery energy storage system. In this way, the dynamic reconfigurable battery system can guide the PCS operation within the safe operation boundary.

Claims

1. A method for bidirectional intelligent coordinated operation of a dynamically reconfigurable battery system and an interconnected energy storage converter, characterized in that: Considering the output voltage, current, and power electrical quantity characteristics of the battery pack in the dynamically reconfigurable battery system, combined with the "power matching" principle and the "reasonable setting of the maintenance factor" principle, in the coupling system of the dynamically reconfigurable battery system and the energy storage converter, hereinafter referred to as the coupling system, the information interaction and two-way intermodulation between the dynamically reconfigurable battery system and the energy storage converter are completed to achieve the optimal operating state of the coupling system; The following steps are involved: S1: According to the topological structure of the dynamically reconfigurable battery system, the electrical quantity characteristics of the output voltage and current of the battery pack in the current state are given; S2: Establish an information interaction mechanism between the dynamic reconfigurable battery system and the energy storage converter, consider the two influencing factors of power supply and demand balance and reasonable selection of battery pack retention factor, and classify the operation mode of the coupling system into six working conditions according to 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 reconstruction strategies for the six working conditions respectively; clarify the energy flow pattern of the coupled system, make the coupled system a real dynamic whole, and realize the optimal operation mode after information interaction.

2. According to claim 1, a method for bidirectional intelligent coordinated operation of a dynamically reconfigurable battery system and an interconnected energy storage converter is characterized in that: The specific method of step S1 is as follows: S1.1: Assume that each battery module in the dynamically reconfigurable battery system is represented by B ij , whose series switch is represented by S ij , the bypass switch is represented by S i ; where i represents the row where the battery module is located, and j represents the column where the battery module is located; where 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; the output voltage and current characteristics of the dynamically reconfigurable battery system are: Where: U dc is the DC voltage, U ij Indicates the battery module terminal voltage at the corresponding position of the corresponding row or column; g ij Indicates the switch status of the corresponding row or column. When the module exits, g ij =0, when the module is put into use g ij =1; P is the output power of the dynamically reconfigurable battery system, I out Output current for dynamically reconfigurable battery systems.

3. According to claim 1, a method for bidirectional intelligent coordinated operation of a dynamically reconfigurable battery system and an interconnected energy storage converter is characterized in that: The specific method of step S2 is as follows: S2.1: It is clear that 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 complete the interaction between the dynamic reconfigurable battery system and the energy storage converter to achieve power balance; the dynamic reconfigurable battery system can change the working state of the battery module in the dynamic reconfigurable battery system by adjusting the retention factor α according to the actual situation, thereby changing the power output range of the dynamic reconfigurable battery system; after receiving different power instructions, the energy storage converter adjusts its own power demand; S2.2: For the selection of the retention factor α, it is necessary to consider the operating temperature, working environment humidity and initial charge state of each battery module; when the operating temperature is higher than 60°C, the self-discharge rate of the battery increases, which may lead to the acceleration of the difference in the state of each battery in the battery pack. At this time, the retention factor requires more frequent balancing operations to maintain battery consistency, so as to ensure the overall stability and efficiency of the dynamically reconfigurable battery system; S2.3: According to the dynamic reconfigurable battery system retention factor and the energy storage inverter power demand in the current state, the system operation modes are divided into six types: "bidirectional optimal", "module optimal", "module optimal, power limit", "power optimal", "power optimal, module limit" and "bidirectional limit".

4. According to claim 1, a method for bidirectional intelligent coordinated operation of a dynamically reconfigurable battery system and an interconnected energy storage converter is characterized in that: The specific method of step S3 is as follows: S3.1: "Bidirectional Optimum" working condition is that the holding factor and the energy storage converter power command do not need to be adjusted. After setting the optimal holding 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" working condition is that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter cannot be met, but adjusting the energy storage converter scheduling instruction can make its power demand meet the output power of the dynamically reconfigurable battery system under the optimal holding factor state; S3.3: The "module is optimal, power is limited" working condition means that the holding factor cannot be adjusted. After setting the optimal holding factor, the power demand of the energy storage converter is adjusted to the limit, but it still cannot match the output power of the dynamic reconfigurable battery system. In this case, the active power dispatch instruction of the energy storage converter should be adjusted according to the maximum output power of the dynamic reconfigurable battery system after reconstruction with the optimal holding factor. If you need to adjust the power demand of the energy storage converter, refer to the following principles: Define the state variables of each battery module as Where x ij Indicates the working state of the battery module, i,j = 1, 2, 3, 4, 5, and the specific value is as shown in formula (3) Then the active power reference value P of the energy storage converter is ref Refer to the following formula for adjustment Where N' is the number of battery modules actually put into operation after reconstruction, SOC' ave is the average value of the state of charge (SOC) of the current dynamically reconfigurable battery system, P' is the current active power dispatch instruction of the energy storage converter; SOC ij is the state of charge of the battery module at the corresponding position of the i-th row and the j-th column; S3.4: The "power optimal" working condition is 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. At this time, the calculation and selection of the holding factor α should be considered again; the suboptimal holding factor α1 of the dynamically reconfigurable battery system should be calculated for this working condition, and the power demand of the energy storage converter should be met after reconfiguration; S3.5: The "power is optimal, the module is limited" working condition is 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. After the holding factor is adjusted to the limit, it still cannot meet the output power demand of the energy storage converter. In this case, the holding factor of the dynamically reconfigurable battery system should be re-set according to the power demand of the energy storage converter; S3.6: "Bidirectional limit" working condition means that the power demand of the energy storage converter and the holding factor of the dynamic reconfigurable battery system can be adjusted; the reconfiguration topology of the dynamic reconfigurable battery system is obtained according to the current holding factor, and the output power of the dynamic reconfigurable battery system is calculated; considering the stability of the coupled system, according to the working priorities of the dynamic reconfigurable battery system and the energy storage converter in the current state, the holding factor of the dynamic reconfigurable battery system and the power demand of the energy storage converter are adjusted respectively; It should be noted that, considering the uncertainty of the system working state, steps S3.1 to S3.6 are overall operating methods under six working conditions in parallel.

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