Energy storage system and charge-discharge power control method thereof

Abstract

This invention relates to the field of energy storage system technology, and its purpose is to provide an energy storage system and its charging and discharging power control method to solve the problem of insufficient flexibility in practical applications of existing energy storage systems. The technical solution can be summarized as follows: an energy storage system includes a control module and at least one energy storage module; each energy storage module includes a first control management module, a first charging and discharging interface, and a battery pack; the first control management module is connected to the battery pack, and the battery pack is connected to the first charging and discharging interface through the first control management module; the control module includes a second control management module and a charging and discharging interface, which are connected; the second control management module is connected to the first control management module of each energy storage module, and the first charging and discharging interface of each energy storage module is connected to the second charging and discharging interface through the second control management module of the control module. The beneficial effect is that it improves the flexibility of the energy storage system in practical applications and is suitable for energy storage systems.

Description

Technical Field

[0001] This invention relates to the field of energy storage system technology, and in particular to an energy storage system and its charging and discharging power control method. Background Technology

[0002] With the rapid development of the new energy industry, the application of energy storage systems such as lithium batteries and nano-cells is becoming increasingly widespread. However, the capacity and load capacity of the battery cells in these systems gradually decrease with usage time and the number of charge-discharge cycles. Therefore, when a single battery module fails and is replaced, the capacity and load capacity of the old and new modules will differ, causing the system to operate at its minimum capacity and / or minimum load capacity, wasting system resources and potentially leading to malfunctions due to battery imbalance. Furthermore, the production cycle for a particular cell model or chemistry is limited. Therefore, once a certain cell model or chemistry is discontinued, the company's sold products will not be covered by after-sales service. These products without after-sales support represent a huge waste of social resources and may also severely damage the company's reputation. Therefore, a flexible electrochemical energy storage system and control method are needed to address these issues. This involves enabling the mixed deployment of old and new batteries or cells, or mixed deployment of cells with different chemistry systems, or mixed deployment of cells with different capacities. This would make current energy storage systems convenient and flexible in practical applications and solve the after-sales service problem.

[0003] In summary, existing energy storage systems suffer from insufficient flexibility in practical applications and difficulty in obtaining after-sales support after battery cell production ceases. Summary of the Invention

[0004] The purpose of this invention is to provide an energy storage system and its charging and discharging power control method to solve the problems of insufficient flexibility in practical applications of existing energy storage systems and difficulty in obtaining after-sales support after the discontinuation of battery cells.

[0005] In the technical solution adopted by the present invention to solve the above-mentioned technical problems, in the first aspect, an energy storage system is provided, including a control module and at least one energy storage module;

[0006] The energy storage module includes a first control and management module, a first charging and discharging interface, and a battery pack consisting of at least one battery cell. The first control and management module is connected to the battery pack, and the battery pack is connected to the first charging and discharging interface through the first control and management module.

[0007] The control module includes a second control management module and a second charging / discharging interface, and the second control management module and the second charging / discharging interface are connected.

[0008] The second control management module is connected to the first control management module of each energy storage module, and the first charging and discharging interface of each energy storage module is connected to the second charging and discharging interface through the second control management module of the control module.

[0009] The first control and management module is used to collect data from its own energy storage module, feed back the data of its own energy storage module to the control module in real time, manage the battery pack of its own energy storage module, and receive and execute control commands from the control module.

[0010] The second control management module is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time and provide human-machine interaction. During discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and allocates the output electrical parameters of each energy storage module in real time in combination with the discharging parameters of the second charging and discharging interface. The allocation status is then sent as a control command to the first control management module of each energy storage module. During charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module. The allocation status is then sent as a control command to the first control management module of each energy storage module.

[0011] In some embodiments, to provide a feasible first control management module, the first control management module includes:

[0012] The system comprises a first control and management unit, a first numerically controlled bidirectional DC-DC converter, a first voltage detection unit, and a first automatic power switch;

[0013] The first control management unit is connected to the monitoring and control management terminal of the battery pack, the detection and control terminal of the first CNC bidirectional DC-DC converter, the data acquisition terminal of the first voltage detection unit, and the control terminal of the first automatic power switch. The input and output terminals of the battery pack are connected to the first bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter. The second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter is connected to the first power terminal of the first automatic power switch. The second power terminal of the first automatic power switch is connected to the detection terminal of the first voltage detection unit and the first charging and discharging interface. The first control management unit communicates with the second control management module of the control module.

[0014] The first control management unit is used to collect data from its energy storage module, feed back the data of its energy storage module to the control module in real time, manage the battery pack of its energy storage module, receive control commands from the control module, control the output electrical parameters of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter according to the corresponding control commands, control the output electrical parameters of the first bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter according to the corresponding control commands, detect the input and output voltage of the first charging and discharging interface through the first voltage detection unit, and cut off or connect the first automatic power switch according to the data of its energy storage module and the data of the first voltage detection unit.

[0015] The first CNC bidirectional DC-DC converter is used to detect and monitor the input and output electrical parameters of its first bidirectional power transmission terminal and second bidirectional power transmission terminal, and send them to the first control management unit according to the detection control terminal. At the same time, during discharge, according to the control of the detection control terminal, the electrical energy received by the first bidirectional power transmission terminal is converted into the corresponding output electrical parameters and output through the second bidirectional power transmission terminal. During charging, according to the control of the detection control terminal, the electrical energy received by the second bidirectional power transmission terminal is converted into the corresponding output electrical parameters and output through the first bidirectional power transmission terminal.

[0016] In some embodiments, to provide data for a feasible energy storage module, the data of the energy storage module includes:

[0017] The corresponding battery pack's real-time state of charge (SOC), real-time state of health (SOH), and input / output electrical parameters; and the corresponding energy storage module's input / output electrical parameters.

[0018] In some embodiments, for the purpose of interpreting the battery management of the battery pack of the energy storage module, the battery management of the battery pack of the energy storage module includes:

[0019] The temperature parameters and input / output electrical parameters of the battery pack are sampled, and protection control is performed in real time according to the cell specifications and corresponding settings of the battery pack.

[0020] In some embodiments, to provide feasible protection control, the sampling of the battery pack's temperature and input / output electrical parameters, and the real-time protection control based on the battery pack's cell specifications and corresponding settings, includes:

[0021] Obtain the cell specifications of the current battery pack to determine the corresponding fault judgment threshold;

[0022] When the temperature and / or input / output electrical parameters of the battery pack obtained from the sampling are used to determine whether the fault determination threshold has been reached, if the threshold is reached, it is determined to be a fault, and the first CNC bidirectional DC-DC converter unit is controlled to stop working; otherwise, the current state is maintained and no processing is performed.

[0023] If the fault continues or worsens after the first CNC bidirectional DC-DC converter unit stops working, the first automatic power switch will be disconnected.

[0024] In some embodiments, to further explain the step of cutting off or connecting the first automatic power switch based on the data of the energy storage module and the data of the first voltage detection unit, the step of cutting off or connecting the first automatic power switch based on the data of the energy storage module and the data of the first voltage detection unit includes:

[0025] During discharge, if the voltage of the first charging / discharging interface is detected to be at a set value, or if the voltage difference between the output voltage of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter and the voltage of the first charging / discharging interface is less than or equal to a preset value, the first automatic power switch is controlled to connect.

[0026] During charging, if the voltage of the first charging / discharging interface is detected to meet the input voltage of the first CNC bidirectional DC-DC converter, the first automatic power switch is controlled to connect.

[0027] In some embodiments, to provide a feasible second control management module, the second control management module includes:

[0028] The system includes a second control and management unit, a human-machine interaction unit, a second voltage detection unit, a current detection unit, a semi-automatic power switch, and an energy transmission terminal for the energy storage module.

[0029] The second control management unit is connected to the human-machine interaction unit, the data acquisition terminal of the current detection unit, the data acquisition terminal of the second voltage detection unit, and the control terminal of the semi-automatic power switch. The second control management unit is also connected to the first control management module of each energy storage module. One end of the semi-automatic power switch is connected to one end of the current detection unit. The other end of the current detection unit is connected to each energy storage module through the energy transmission terminal of the energy storage module and is connected to the first detection terminal of the second voltage detection unit. The other end of the semi-automatic power switch is connected to the second charging and discharging interface and is connected to the second detection terminal of the second voltage detection unit.

[0030] The second control management unit is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the current detection unit, determine whether to cut off the semi-automatic power switch, and provide human-machine interaction through the human-machine interaction unit; during discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and allocates the output electrical parameters of each energy storage module in real time in combination with the discharging parameters of the second charging and discharging interface, and sends the allocation status as a control command to the first control management module of each energy storage module; during charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module.

[0031] In some embodiments, to further enhance safety redundancy, the second control management module further includes a second automatic power switch;

[0032] The connection between one end of the semi-automatic power switch and one end of the current detection unit means that one end of the semi-automatic power switch is connected to one end of the current detection unit through a second automatic power switch.

[0033] The control terminal of the second automatic power switch is connected to the second control management unit;

[0034] The third detection terminal of the second voltage detection unit is connected to the end where the semi-automatic power switch is connected to the second automatic power switch;

[0035] The second control management unit is also used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the current detection unit, and to determine whether to cut off the second automatic power switch.

[0036] In some embodiments, to provide another feasible second control management module, the second control management module includes:

[0037] The system includes a second control and management unit, a human-machine interaction unit, a second voltage detection unit, a second numerically controlled bidirectional DC-DC converter, a semi-automatic power switch, and an energy transmission terminal for the energy storage module.

[0038] The second control management unit is connected to the human-machine interaction unit, the data acquisition terminal of the second voltage detection unit, the detection control terminal of the second CNC bidirectional DC-DC converter, and the control terminal of the semi-automatic power switch. The second control management unit is connected to the first control management module of each energy storage module. The first bidirectional power transmission terminal of the second CNC bidirectional DC-DC converter is connected to each energy storage module through the power transmission terminal of the energy storage module and is connected to the first detection terminal of the second voltage detection unit. The second bidirectional power transmission terminal of the second CNC bidirectional DC-DC converter is connected to one end of the semi-automatic power switch and to the third detection terminal of the second voltage detection unit. The other end of the semi-automatic power switch is connected to the second charging and discharging interface and to the second detection terminal of the second voltage detection unit.

[0039] The second control management unit is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the second CNC bidirectional DC-DC converter, and to provide human-machine interaction through the human-machine interaction unit. During discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and, in conjunction with the discharging parameters of the second charging and discharging interface, allocates the output electrical parameters of each energy storage module in real time, and sends the allocation status as a control command to the first control management module of each energy storage module. It also compares the input electrical parameters of the second CNC bidirectional DC-DC converter with the target output electrical parameters in real time, and adjusts the output electrical parameters of the second CNC bidirectional DC-DC converter to the target output electrical parameters. During charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module. At the same time, it acquires the charging parameters, and adjusts the output electrical parameters of the second CNC bidirectional DC-DC converter to the charging parameters in real time according to the input electrical parameters of the second CNC bidirectional DC-DC converter and the charging parameters.

[0040] In some embodiments, to provide feasible charging parameters, the charging parameters include: maximum charging voltage; and also include maximum charging power and / or maximum charging current.

[0041] In some embodiments, to provide a feasible target output electrical parameter, the target output electrical parameter includes: a target output voltage; and further includes: a target output current and / or a target output power.

[0042] In the second aspect of the technical solution adopted by the present invention to solve the above-mentioned technical problems, a charging and discharging power control method for an energy storage system is provided, applied to the above-mentioned energy storage system, comprising:

[0043] During discharge:

[0044] The second control and management module obtains the target output voltage and target output power based on the target output electrical parameters, and obtains data for each energy storage module, including at least the maximum output power, initial maximum energy storage capacity, real-time state of charge, and real-time health of each energy storage module.

[0045] The target output power of each energy storage module is calculated based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status.

[0046] The target output voltage and the target output power of each energy storage module are sent to the first control and management module of each corresponding energy storage module.

[0047] After receiving the target output power and target output voltage of the module, the first control and management module of each energy storage module adjusts its own output electrical parameters to the target output power and target output voltage of the module, and each energy storage module operates in the discharge state.

[0048] During charging:

[0049] The second control and management module sends a charging command to the first control and management module of each energy storage module. If the current state of each energy storage module meets the charging conditions, it will operate in the charging state.

[0050] Acquire data for each energy storage module, including at least the maximum input power, initial maximum energy storage capacity, and real-time health status of each energy storage module;

[0051] The maximum power allocation value of each energy storage module is calculated based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status.

[0052] When each energy storage module is in charging mode, its own charging power gradually increases from the preset safety parameter, and during the increase, the input power of each energy storage module is always less than or equal to the maximum power allocation value.

[0053] In some embodiments, to provide a feasible method for calculating the target output power of each energy storage module based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status, the step of calculating the target output power of each energy storage module based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status includes:

[0054] The target output power of each energy storage module is calculated using the following formula:

[0055] ;

[0056] Where Pdx refers to the target output power of the x-th energy storage module, P L This refers to the target output power, Pdx max This refers to the maximum output power of the x-th energy storage module, Pdi max This refers to the maximum output power of the i-th energy storage module, Qx max This refers to the initial maximum electrical energy storage capacity of the x-th energy storage module, Qi. max SOCx refers to the initial maximum energy storage capacity of the i-th energy storage module, SOCi refers to the real-time state of charge of the x-th energy storage module, SOHx refers to the real-time health of the x-th energy storage module, SOHi refers to the real-time health of the i-th energy storage module, and n is the total number of energy storage modules.

[0057] In some embodiments, since the target output power of the energy storage module calculated according to the above calculation formula may be greater than the maximum output power of the energy storage module, when the calculated target output power of the energy storage module is greater than the maximum output power of the corresponding energy storage module, the maximum output power of the corresponding energy storage module is taken as the target output power of the energy storage module and recorded as a fixed value. At the same time, the target output power minus the fixed value is used as the new target output power and substituted into the above calculation formula. After eliminating the corresponding energy storage module, the target output power of the remaining energy storage modules is recalculated.

[0058] In some embodiments, in any energy storage module, since the performance of the battery pack changes with the usage time, the target output power of the module may still be greater than the real-time maximum output power of the energy storage module. Therefore, in order to further guarantee the output power, when any first control management module detects that its energy storage module has reached the real-time maximum output power, it sends the real-time maximum output power and the information of the maximum output power reached to the second control management module.

[0059] After receiving the information that the maximum output power has been reached, the second control and management module updates the maximum output power of the corresponding energy storage module using the real-time maximum output power, and recalculates the target output power of each energy storage module based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status.

[0060] In some embodiments, to provide a feasible method for calculating the maximum power allocation value of each energy storage module based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status, the step of calculating the maximum power allocation value of each energy storage module based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status includes:

[0061] The maximum power allocation value for each energy storage module is calculated using the following formula:

[0062] ;

[0063] Where Pcx refers to the maximum power allocation value of the x-th energy storage module, P CHG This refers to the total maximum input power, Pcx. max This refers to the maximum input power of the x-th energy storage module, Pci max This refers to the maximum input power of the i-th energy storage module, Qx max This refers to the initial maximum electrical energy storage capacity of the x-th energy storage module, Qi. max SOHx refers to the maximum energy storage capacity of the i-th energy storage module, SOHi refers to the real-time health status of the x-th energy storage module, and SOHi refers to the real-time health status of the i-th energy storage module.

[0064] The beneficial effects of this invention are that, in the solution of this invention, a control module and at least one energy storage module are adopted, and each energy storage module is independent of the others. It is only necessary to ensure that each independent energy storage module uses batteries or cells of the same capacity, the same chemical system, and the same new and old batteries or cells to form a battery pack. The cells in different energy storage modules can have different capacities, different chemical systems, and different new and old cells, thereby enabling the mixed deployment of cells of different capacities and / or cells of different chemical systems and / or new and old batteries or cells in the entire energy storage system. This improves the flexibility of the energy storage system in practical applications and also solves the after-sales problems caused by the discontinuation of cell production. Attached Figure Description

[0065] Figure 1 This is a schematic system block diagram of the energy storage system in an embodiment of the present invention.

[0066] Figure 2 This is a schematic system block diagram of an energy storage system in another embodiment of the present invention.

[0067] Figure 3 This is a schematic system block diagram of an energy storage system in another embodiment of the present invention. Detailed Implementation

[0068] The technical solution of the present invention will now be described in detail with reference to the embodiments and accompanying drawings.

[0069] like Figure 1 As shown in the embodiments of the present invention, in a first aspect, an energy storage system is provided, including a control module and at least one energy storage module;

[0070] The energy storage module includes a first control and management module, a first charging and discharging interface, and a battery pack consisting of at least one battery cell. The first control and management module is connected to the battery pack, and the battery pack is connected to the first charging and discharging interface through the first control and management module.

[0071] The control module includes a second control management module and a second charging / discharging interface, and the second control management module and the second charging / discharging interface are connected.

[0072] The second control management module is connected to the first control management module of each energy storage module, and the first charging and discharging interface of each energy storage module is connected to the second charging and discharging interface through the second control management module of the control module.

[0073] The first control and management module is used to collect data from its own energy storage module, feed back the data of its own energy storage module to the control module in real time, manage the battery pack of its own energy storage module, and receive and execute control commands from the control module.

[0074] The second control management module is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time and provide human-machine interaction. During discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and allocates the output electrical parameters of each energy storage module in real time in combination with the discharging parameters of the second charging and discharging interface. The allocation status is then sent as a control command to the first control management module of each energy storage module. During charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module. The allocation status is then sent as a control command to the first control management module of each energy storage module.

[0075] It is understood that in the above embodiments, the first charging and discharging interfaces of each energy storage module are connected in parallel. Therefore, when a certain energy storage module fails, it is only necessary to shut down the first digitally controlled bidirectional DC-DC converter and / or disconnect the first automatic power switch of that energy storage module, without affecting other energy storage modules. The second control and management module allocates the input and output electrical parameters of each energy storage module in real time. Therefore, when a single subsystem (energy storage module) fails or is damaged, it will not affect the normal operation of the parent system (energy storage system). At the same time, because the first charging and discharging interfaces of each energy storage module are connected in parallel, the battery cells used in each energy storage module can be different. For example, the battery cells in one energy storage module are lithium iron phosphate, while the battery cells in another energy storage module are ternary lithium, lithium titanate, sodium batteries, or lithium batteries, etc. Their newness and age can also be different. For example, the battery cells in one energy storage module are all brand new batteries of a certain model, while the battery cells in another energy storage module are all batteries of a certain model with a certain degree of use, etc. In addition, the first control and management module in each energy storage module also manages the corresponding battery pack. That is, the battery management in each energy storage module is the responsibility of its own first control and management module, and the energy storage modules will not affect each other.

[0076] As can be seen, in the above embodiments, it is only necessary to ensure that the same battery cell is used in a single energy storage module. Therefore, various batteries or cells can be flexibly deployed in the actual use of the entire energy storage system, which improves the flexibility of the energy storage system during use.

[0077] See Figure 2 or Figure 3 In some embodiments, to provide a feasible first control management module, the first control management module may include:

[0078] The system comprises a first control and management unit, a first numerically controlled bidirectional DC-DC converter, a first voltage detection unit, and a first automatic power switch;

[0079] The first control management unit is connected to the monitoring and control management terminal of the battery pack, the detection and control terminal of the first CNC bidirectional DC-DC converter, the data acquisition terminal of the first voltage detection unit, and the control terminal of the first automatic power switch. The input and output terminals of the battery pack are connected to the first bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter. The second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter is connected to the first power terminal of the first automatic power switch. The second power terminal of the first automatic power switch is connected to the detection terminal of the first voltage detection unit and the first charging and discharging interface. The first control management unit communicates with the second control management module of the control module.

[0080] The first control management unit is used to collect data from its energy storage module, feed back the data of its energy storage module to the control module in real time, manage the battery pack of its energy storage module, receive control commands from the control module, control the output electrical parameters of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter according to the corresponding control commands, control the output electrical parameters of the first bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter according to the corresponding control commands, detect the input and output voltage of the first charging and discharging interface through the first voltage detection unit, and cut off or connect the first automatic power switch according to the data of its energy storage module and the data of the first voltage detection unit.

[0081] The first CNC bidirectional DC-DC converter is used to detect and monitor the input and output electrical parameters of its first bidirectional power transmission terminal and second bidirectional power transmission terminal, and send them to the first control management unit according to the detection control terminal. At the same time, during discharge, according to the control of the detection control terminal, the electrical energy received by the first bidirectional power transmission terminal is converted into the corresponding output electrical parameters and output through the second bidirectional power transmission terminal. During charging, according to the control of the detection control terminal, the electrical energy received by the second bidirectional power transmission terminal is converted into the corresponding output electrical parameters and output through the first bidirectional power transmission terminal.

[0082] It is understood that the above embodiments provide a feasible first control and management module for a related energy storage module. This module employs a first bidirectional digital-controlled DC-DC converter to convert the output electrical parameters of the energy storage module into the required electrical parameters sent by the second control and management module (i.e., converting the electrical energy received by the first bidirectional power transmission terminal into corresponding output electrical parameters and outputting them through the second bidirectional power transmission terminal). It can also convert the input electrical energy into electrical energy required for battery charging (i.e., converting the electrical energy received by the second bidirectional power transmission terminal into corresponding output electrical parameters and outputting them through the first bidirectional power transmission terminal). Furthermore, the first control and management unit manages the electrical parameters within the energy storage module. The battery pack performs battery management, such as sampling the temperature parameters and input / output electrical parameters (voltage and / or current) of the battery pack, and performing protection control in real time according to the cell specifications and corresponding settings of the battery pack. It can be seen that when this energy storage module adopts this first control management module, it only receives the control from the control module. The specific processing, control and protection of the input electrical parameters (charging state) of the battery pack and the output electrical parameters (discharging state) of the energy storage module are all completed by the first control management unit. It is isolated from other energy storage modules and will not affect each other. The control module does not need to care about the type of battery cells used in each energy storage module, which improves the flexibility of use.

[0083] The purpose of adding a voltage detection module here is to prevent the inability to collect the corresponding voltage data when the first CNC bidirectional DC-DC converter unit fails, thereby further improving safety and the accuracy of the collected data.

[0084] It should be noted that all input electrical parameters, output electrical parameters, and charging parameters should at least include the corresponding voltage value, and may also include various required electrical parameters, such as the corresponding current value and / or the corresponding discharge power and / or the corresponding charging power.

[0085] The data from the energy storage module may include:

[0086] The corresponding battery pack's real-time state of charge (SOC), real-time state of health (SOH), and input / output electrical parameters; as well as the corresponding energy storage module's input / output electrical parameters, etc.

[0087] Here, the data from the energy storage module can also include the state of power (SOP), etc.

[0088] In addition, the temperature and input / output electrical parameters of the battery pack are sampled, and protection control is performed in real time according to the cell specifications and corresponding settings of the battery pack, which may include:

[0089] Obtain the cell specifications of the current battery pack to determine the corresponding fault judgment threshold;

[0090] When the temperature and / or input / output electrical parameters of the battery pack obtained from the sampling are used to determine whether the fault determination threshold has been reached, if the threshold is reached, it is determined to be a fault, and the first CNC bidirectional DC-DC converter unit is controlled to stop working; otherwise, the current state is maintained and no processing is performed.

[0091] If the fault continues or worsens after the first CNC bidirectional DC-DC converter unit stops working, the first automatic power switch will be disconnected.

[0092] It is understood that the fault determination thresholds here may include undervoltage threshold, overvoltage threshold, overtemperature threshold, low temperature threshold, power threshold, and short circuit threshold, etc. This is existing technology and will not be described in detail here.

[0093] In addition, the "expansion" of the fault here can be understood as such as the undervoltage continuing to increase, the overcurrent continuing to increase, the temperature continuing to rise, and the short-circuit current continuing to increase.

[0094] After the first automatic power switch is turned off, the energy storage module is disconnected from the entire energy storage system and is no longer indirectly connected to the second charging and discharging interface of the control module.

[0095] To further explain the above-mentioned disconnection or connection of the first automatic power switch based on the data of the energy storage module and the data of the first voltage detection unit, disconnection or connection of the first automatic power switch based on the data of the energy storage module and the data of the first voltage detection unit may include:

[0096] During discharge, if the voltage of the first charging / discharging interface is detected to be at a set value, or if the voltage difference between the output voltage of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter and the voltage of the first charging / discharging interface is less than or equal to a preset value, the first automatic power switch is controlled to connect.

[0097] During charging, if the voltage of the first charging / discharging interface is detected to meet the input voltage of the first CNC bidirectional DC-DC converter, the first automatic power switch is controlled to connect.

[0098] It is understandable that the setting value here refers to a certain special voltage. For example, when the first energy storage module to be connected during discharge, the voltage input to the control module should be 0V. Then, the voltage at the first charging and discharging interface of each energy storage module is 0V or close to 0V, so the setting value can be set to around 0V.

[0099] Since each energy storage module has a first CNC bidirectional DC-DC converter, when it is in the discharge state, even if the output voltages of each energy storage module are not perfectly matched, it may cause a momentary reverse charge to the energy storage module with the lower output voltage. However, this reverse charge will quickly raise the first charge and discharge interface voltage of the energy storage module. At the same time, the energy storage module will continue to increase the output voltage to the target output voltage until it outputs the corresponding target power, which will not cause too much impact. Therefore, when the voltage difference between the output voltage of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter and the voltage of the first charge and discharge interface is less than or equal to a preset value (such as ±10V), the first automatic power switch can be connected, so that the output power of the energy storage module is incorporated into the bus that transmits power to the control module.

[0100] See Figure 2 In some embodiments, to provide a feasible second control management module, the second control management module may include:

[0101] The system includes a second control and management unit, a human-machine interaction unit, a second voltage detection unit, a current detection unit, a semi-automatic power switch, and an energy transmission terminal for the energy storage module.

[0102] The second control management unit is connected to the human-machine interaction unit, the data acquisition terminal of the current detection unit, the data acquisition terminal of the second voltage detection unit, and the control terminal of the semi-automatic power switch. The second control management unit is also connected to the first control management module of each energy storage module. One end of the semi-automatic power switch is connected to one end of the current detection unit. The other end of the current detection unit is connected to each energy storage module through the energy transmission terminal of the energy storage module and is connected to the first detection terminal of the second voltage detection unit. The other end of the semi-automatic power switch is connected to the second charging and discharging interface and is connected to the second detection terminal of the second voltage detection unit.

[0103] The second control management unit is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the current detection unit, determine whether to cut off the semi-automatic power switch, and provide human-machine interaction through the human-machine interaction unit; during discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and allocates the output electrical parameters of each energy storage module in real time in combination with the discharging parameters of the second charging and discharging interface, and sends the allocation status as a control command to the first control management module of each energy storage module; during charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module.

[0104] It is understood that the above embodiments provide a feasible second control management module for the control module. During discharge, this module acquires the target output electrical parameters and the data currently received from each energy storage module. Combining this with the discharge parameters of the second charging / discharging interface, it allocates the output electrical parameters of each energy storage module in real time and sends the allocation status as a control command to the first control management module of each energy storage module. During charging, it allocates the input electrical parameters of each energy storage module in real time based on the charging parameters of the second charging / discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module. In other words, the main function of the second control management unit is to allocate the input and output electrical parameters of each energy storage module, performing a unified and coordinated function. It does not directly operate on the specific operation of each energy storage module; therefore, when a certain energy storage module malfunctions, it will not affect the control module.

[0105] Meanwhile, since the output electrical parameters of each energy storage module are allocated in real time during discharge and the input electrical parameters of each energy storage module are also allocated in real time during charging, that is to say, when one or more energy storage modules fail and disconnect the power transmission with the control module, the control module can reallocate the power according to the currently intact energy storage modules. The control module can determine whether the energy storage module is normal by using the data of the aforementioned energy storage modules. If any energy storage module disconnects its power transmission with the control module due to a failure, it can simultaneously send the fault or disconnection data as the current energy storage module data to the control module. This is existing technology and will not be described in detail here.

[0106] The first, second, and third detection terminals of the second voltage detection unit are respectively located at the power transmission end of the energy storage module and at both ends of the semi-automatic power switch. The purpose is to allow the second control and management unit to further determine which unit or component has a problem and whether the semi-automatic power switch should be cut off in case of a fault.

[0107] In some embodiments, to further enhance safety redundancy, the second control management module may also include a second automatic power switch;

[0108] The connection between one end of the semi-automatic power switch and one end of the current detection unit means that one end of the semi-automatic power switch is connected to one end of the current detection unit through a second automatic power switch.

[0109] The control terminal of the second automatic power switch is connected to the second control management unit;

[0110] The third detection terminal of the second voltage detection unit is connected to the end where the semi-automatic power switch is connected to the second automatic power switch;

[0111] The second control management unit is also used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the current detection unit, and to determine whether to cut off the second automatic power switch.

[0112] It is understandable that, referring to the above embodiments, since the semi-automatic power switch can only be manually turned on, while its disconnection can be controlled manually or by the second control management unit, in some cases, such as instantaneous power surges, it may be necessary to automatically turn on or off the input or output of the entire energy storage system. Therefore, this automatic power switch is added. In specific applications, the second control management unit should first control the automatic power switch. If the automatic power switch is ineffective, then control the semi-automatic power switch. If the control module detects abnormalities in its own input or output electrical parameters and considers a fault to have occurred, it should first disconnect the automatic power switch. If the fault is eliminated, the automatic power switch should be turned on again. If the fault is not eliminated and continues to worsen, the semi-automatic power switch should be disconnected. This improves safety redundancy.

[0113] See Figure 3 In some embodiments, to provide another feasible second control management module, the second control management module may include:

[0114] The system includes a second control and management unit, a human-machine interaction unit, a second voltage detection unit, a second numerically controlled bidirectional DC-DC converter, a semi-automatic power switch, and an energy transmission terminal for the energy storage module.

[0115] The second control management unit is connected to the human-machine interaction unit, the data acquisition terminal of the second voltage detection unit, the detection control terminal of the second CNC bidirectional DC-DC converter, and the control terminal of the semi-automatic power switch. The second control management unit is connected to the first control management module of each energy storage module. The first bidirectional power transmission terminal of the second CNC bidirectional DC-DC converter is connected to each energy storage module through the power transmission terminal of the energy storage module and is connected to the first detection terminal of the second voltage detection unit. The second bidirectional power transmission terminal of the second CNC bidirectional DC-DC converter is connected to one end of the semi-automatic power switch and to the third detection terminal of the second voltage detection unit. The other end of the semi-automatic power switch is connected to the second charging and discharging interface and to the second detection terminal of the second voltage detection unit.

[0116] The second control management unit is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the second CNC bidirectional DC-DC converter, and to provide human-machine interaction through the human-machine interaction unit. During discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and, in conjunction with the discharging parameters of the second charging and discharging interface, allocates the output electrical parameters of each energy storage module in real time, and sends the allocation status as a control command to the first control management module of each energy storage module. It also compares the input electrical parameters of the second CNC bidirectional DC-DC converter with the target output electrical parameters in real time, and adjusts the output electrical parameters of the second CNC bidirectional DC-DC converter to the target output electrical parameters. During charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module. At the same time, it acquires the charging parameters, and adjusts the output electrical parameters of the second CNC bidirectional DC-DC converter to the charging parameters in real time according to the input electrical parameters of the second CNC bidirectional DC-DC converter and the charging parameters.

[0117] It is understood that, compared with the second control management module mentioned in the above embodiments, this embodiment only replaces the current detection unit with a second CNC bidirectional DC-DC converter unit. The advantage of this replacement is that if the voltage value input to the energy transmission terminal of the energy storage module does not meet the target output voltage during discharge, the second CNC bidirectional DC-DC converter unit can be used to further convert the voltage value. The second CNC bidirectional DC-DC converter unit itself has functions such as current detection, voltage detection and power detection, so there is no need to use a current detection unit.

[0118] The charging parameters here may include: maximum charging voltage; and may also include maximum charging power and / or maximum charging current, etc.

[0119] The target output electrical parameters may include: target output voltage; and may also include: target output current and / or target output power, etc.

[0120] In practical use, the above embodiments can provide various fault tolerance and redundancy protections, such as:

[0121] When the first control and management module of each energy storage module detects a fault such as undervoltage, overcurrent and / or overtemperature in the battery pack directly connected to it, if there is a first CNC bidirectional DC-DC converter module, it can first control the first CNC bidirectional DC-DC converter module to stop working. If the fault continues or expands or there is no first CNC bidirectional DC-DC converter module, the power transmission between the energy storage module and the energy storage system can be cut off by means of the first automatic power switch, etc., to achieve the first level of fault protection.

[0122] Meanwhile, if the control module detects a fault in a certain energy storage module based on the data from each energy storage module, it can also directly notify the energy storage module to cut off the power transmission between the energy storage module and the energy storage system through the communication connection with the energy storage module, thereby achieving the second level of fault protection.

[0123] If the energy storage module has cut off the power transmission with the energy storage system, and the control module detects that the fault has further expanded, then if a second automatic power switch is present, the second automatic power switch will be cut off to achieve the third level of fault protection.

[0124] If the fault continues to escalate after the second automatic power switch is turned off, the control module can cut off the power transmission of the energy storage system by turning off the semi-automatic power switch, thus achieving the fourth level of fault protection.

[0125] Of course, if staff discover a fault in a certain area through human-computer interaction, they can also directly cut off the power transmission of the energy storage system through semi-automatic power switches or other means.

[0126] In a second aspect of this invention, a method for controlling the charging and discharging power of an energy storage system is provided, applied to the aforementioned energy storage system, comprising:

[0127] During discharge:

[0128] The second control and management module obtains the target output voltage and target output power based on the target output electrical parameters, and obtains data for each energy storage module, including at least the maximum output power, initial maximum energy storage capacity, real-time state of charge, and real-time health of each energy storage module.

[0129] The target output power of each energy storage module is calculated based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status.

[0130] The target output voltage and the target output power of each energy storage module are sent to the first control and management module of each corresponding energy storage module.

[0131] After receiving the target output power and target output voltage of the module, the first control and management module of each energy storage module adjusts its own output electrical parameters to the target output power and target output voltage of the module, and each energy storage module operates in the discharge state.

[0132] During charging:

[0133] The second control and management module sends a charging command to the first control and management module of each energy storage module. If the current state of each energy storage module meets the charging conditions, it will operate in the charging state.

[0134] Acquire data for each energy storage module, including at least the maximum input power, initial maximum energy storage capacity, and real-time health status of each energy storage module;

[0135] The maximum power allocation value of each energy storage module is calculated based on the total input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status.

[0136] When each energy storage module is in charging mode, its own charging power gradually increases from the preset safety parameter, and during the increase, the input power of each energy storage module is always less than or equal to the maximum power allocation value.

[0137] Understandably, since the maximum output power, initial maximum energy storage, real-time state of charge, and real-time health are all commonly used data in energy storage systems or modules, and are closely related to their discharge and charging efficiency, the target output power of each energy storage module can be determined based on its maximum output power, maximum energy storage, real-time state of charge, and real-time health during discharge. During charging, the maximum power allocation value of each energy storage module can be calculated based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage, and the real-time health.

[0138] Since the target output voltage is known during discharge and the power transmission terminals of each energy storage module are connected in parallel, the output voltage of each energy storage module needs to be as close as possible to the target output voltage. Of course, the target output voltage here can also be other voltages that the control module tells each energy storage module. This is because if the actual target output voltage exceeds the maximum adjustment voltage value of some energy storage modules, in order to unify the output voltage of each energy storage module as much as possible, the target output voltage sent to each energy storage module needs to be lowered. In order to make the final output voltage of the energy storage system correspond to the target output voltage, a second digitally controlled bidirectional DC-DC converter module can be used in the control module for conversion again in the manner described in the above embodiment.

[0139] During charging, the energy storage module may use battery cells with different rates, capacities, chemical systems, and health conditions, and the charging requirements of different cells may vary. For example, some cells require constant current charging followed by constant voltage charging, while others require constant power charging throughout, or even trickle charging when the cell voltage drops below a certain value. Therefore, the second control and management module only allocates the maximum charging power for each module; the actual charging method and power are determined by the energy storage module based on the battery cells and their status. The total maximum input power here refers to the maximum input power of the energy storage system, which is related to hardware devices such as interfaces.

[0140] In some embodiments, to provide a feasible method for calculating the target output power of each energy storage module based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status, the maximum power allocation value can include:

[0141] The target output power of each energy storage module is calculated using the following formula:

[0142] ;

[0143] Where Pdx refers to the target output power of the x-th energy storage module, P L This refers to the target output power, Pdx max This refers to the maximum output power of the x-th energy storage module, Pdi max This refers to the maximum output power of the i-th energy storage module, Qx max This refers to the initial maximum electrical energy storage capacity of the x-th energy storage module, Qi. max SOCx refers to the initial maximum energy storage capacity of the i-th energy storage module, SOCi refers to the real-time state of charge of the x-th energy storage module, SOHx refers to the real-time health of the x-th energy storage module, SOHi refers to the real-time health of the i-th energy storage module, and n is the total number of energy storage modules.

[0144] It is understandable that, since the real-time discharge power of an energy storage system is equal to the sum of the discharge power of all energy storage modules within the system, when the real-time discharge power of the energy storage system equals the target output power, the following formula applies:

[0145] ;

[0146] As can be seen, by substituting the above formula, the target output power of each energy storage module can be calculated using the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status.

[0147] In some embodiments, since the target output power of the energy storage module calculated according to the above calculation formula may be greater than the maximum output power of the energy storage module, which may lead to failure to operate normally or cause safety hazards, when the calculated target output power of the energy storage module is greater than the maximum output power of the corresponding energy storage module, the maximum output power of the corresponding energy storage module is taken as the target output power of the energy storage module and recorded as a fixed value. At the same time, the target output power minus the fixed value is used as the new target output power and substituted into the above calculation formula. After eliminating the corresponding energy storage module, the target output power of the remaining energy storage modules is recalculated.

[0148] It is understood that the above embodiment means that, assuming the target output power of the j-th energy storage module is Pdj, then the maximum output power of the corresponding energy storage module is Pdj. max The corresponding initial maximum energy storage capacity of this energy storage module is Qj. max The corresponding real-time state of charge of the energy storage module is SOCx, and the corresponding real-time health status of the energy storage module is SOHj.

[0149] When Pdj > Pdj max When, replace Pdj with Pdj max The value;

[0150] The target output power of the remaining energy storage modules is recalculated using the following formula:

[0151] ;

[0152] This ensures that the target output power of all calculated energy storage modules is less than or equal to the maximum output power of the corresponding energy storage module.

[0153] In some embodiments, in any energy storage module, since the performance of the battery pack changes with the usage time, the target output power of the module may still be greater than the real-time maximum output power of the energy storage module. Therefore, in order to further guarantee the output power, when any first control management module detects that its energy storage module has reached the real-time maximum output power, it sends the real-time maximum output power and the information of the maximum output power reached to the second control management module.

[0154] After receiving the information that the maximum output power has been reached, the second control and management module updates the maximum output power of the corresponding energy storage module using the real-time maximum output power, and recalculates the target output power of each energy storage module based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status.

[0155] It is understandable that the recalculation of the target output power of each energy storage module based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status can be performed using the calculation formula mentioned in the above embodiments. Alternatively, the target output power can be subtracted from the real-time maximum output power, and then this new target output power can be substituted into the above calculation formula. After removing the corresponding energy storage module, the target output power of the remaining energy storage modules can be recalculated. In other words, a calculation method similar to that used in the above embodiments, where the target output power of an energy storage module is greater than the maximum output power of the corresponding energy storage module, is used to redistribute the target output power of the modules.

[0156] In some embodiments, to provide a feasible method for calculating the maximum power allocation value of each energy storage module based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status, the calculation of the maximum power allocation value of each energy storage module based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status may include:

[0157] The maximum power allocation value for each energy storage module is calculated using the following formula:

[0158] ;

[0159] Where Pcx refers to the maximum power allocation value of the x-th energy storage module, P CHG This refers to the total maximum input power, Pcx. max This refers to the maximum input power of the x-th energy storage module, Pci max This refers to the maximum input power of the i-th energy storage module, Qx max This refers to the initial maximum electrical energy storage capacity of the x-th energy storage module, Qi. max SOHx refers to the maximum energy storage capacity of the i-th energy storage module, SOHi refers to the real-time health status of the x-th energy storage module, and SOHi refers to the maximum power allocation value of the real-time health status of the i-th energy storage module.

[0160] It is understandable that, without considering hardware limitations, the total maximum charging power of the energy storage system should be equal to the sum of the charging power of all energy storage modules within the system, which is denoted here as P. CHG The following formula exists:

[0161] ;

[0162] As can be seen, by substituting the above formula, the maximum power allocation value corresponding to each energy storage module can be calculated using the total maximum input power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status.

[0163] Furthermore, since the first charging and discharging interface of all energy storage modules is directly connected to the control module, the control module cannot actually control the actual input power of each energy storage module during charging. Therefore, the above formula aims to allocate the available charging power of the energy storage system, and does not control whether the energy storage modules must be charged according to the maximum power allocation value. The energy storage modules are charged according to their own cell requirements, state, or control strategy requirements, using either constant voltage followed by constant current, constant power, trickle charging followed by constant current followed by constant voltage, or trickle charging followed by constant power.

[0164] Here, to avoid potential safety hazards when the maximum power allocation value exceeds the maximum input power of the corresponding energy storage module, the maximum power allocation value should be less than or equal to the maximum input power of the energy storage module. Similarly, during discharge, if the maximum power allocation value of a certain energy storage module exceeds its maximum input power, the maximum power allocation value of that module can be set to that maximum input power. The total maximum input power is then subtracted from this maximum input power, and this new total maximum input power is substituted into the above formula. After removing the corresponding energy storage module, the maximum power allocation value of the remaining energy storage modules is recalculated. In other words, the maximum power allocation values ​​of the remaining energy storage modules are redistributed. The specific calculation method can be as follows:

[0165] Assuming the maximum power allocation value of the j-th energy storage module is Pcj, then the corresponding maximum input power of that energy storage module is Pcj. max The corresponding initial maximum energy storage capacity of this energy storage module is Qj. max The corresponding real-time health status of the energy storage module is SOHj;

[0166] When Pcj > Pcj max When, replace Pcj with Pcj max The value;

[0167] The target output power of the remaining energy storage modules is recalculated using the following formula:

[0168] ;

[0169] This ensures that the maximum power allocation value of all calculated energy storage modules is less than or equal to the maximum input power of the corresponding energy storage module.

Claims

1. An energy storage system, characterized in that, It includes a control module and at least one energy storage module; The energy storage module includes a first control and management module, a first charging and discharging interface, and a battery pack consisting of at least one battery cell. The first control and management module is connected to the battery pack, and the battery pack is connected to the first charging and discharging interface through the first control and management module. The control module includes a second control management module and a second charging / discharging interface, and the second control management module and the second charging / discharging interface are connected. The second control management module is connected to the first control management module of each energy storage module, and the first charging and discharging interface of each energy storage module is connected to the second charging and discharging interface through the second control management module of the control module. The first control and management module is used to collect data from its own energy storage module, feed back the data of its own energy storage module to the control module in real time, manage the battery pack of its own energy storage module, and receive and execute control commands from the control module. The second control management module is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time and provide human-machine interaction; during discharging, it acquires the target output electrical parameters and the data of each energy storage module currently received, and in combination with the discharging parameters of the second charging and discharging interface, allocates the output electrical parameters of each energy storage module in real time, and sends the allocation status as a control command to the first control management module of each energy storage module. During charging, the input electrical parameters of each energy storage module are allocated in real time based on the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module. The allocation status is then sent as a control command to the first control management module of each energy storage module.

2. The energy storage system as described in claim 1, characterized in that, The first control and management module includes: The system comprises a first control and management unit, a first numerically controlled bidirectional DC-DC converter, a first voltage detection unit, and a first automatic power switch; The first control management unit is connected to the monitoring and control management terminal of the battery pack, the detection and control terminal of the first CNC bidirectional DC-DC converter, the data acquisition terminal of the first voltage detection unit, and the control terminal of the first automatic power switch. The input and output terminals of the battery pack are connected to the first bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter. The second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter is connected to the first power terminal of the first automatic power switch. The second power terminal of the first automatic power switch is connected to the detection terminal of the first voltage detection unit and the first charging and discharging interface. The first control management unit communicates with the second control management module of the control module. The first control management unit is used to collect data from its energy storage module, feed back the data of its energy storage module to the control module in real time, manage the battery pack of its energy storage module, receive control commands from the control module, control the output electrical parameters of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter according to the corresponding control commands, control the output electrical parameters of the first bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter according to the corresponding control commands, detect the input and output voltage of the first charging and discharging interface through the first voltage detection unit, and cut off or connect the first automatic power switch according to the data of its energy storage module and the data of the first voltage detection unit. The first CNC bidirectional DC-DC converter is used to detect and monitor the input and output electrical parameters of its first bidirectional power transmission terminal and second bidirectional power transmission terminal, and send them to the first control management unit according to the detection control terminal. At the same time, during discharge, according to the control of the detection control terminal, the electrical energy received by the first bidirectional power transmission terminal is converted into the corresponding output electrical parameters and output through the second bidirectional power transmission terminal. During charging, according to the control of the detection control terminal, the electrical energy received by the second bidirectional power transmission terminal is converted into the corresponding output electrical parameters and output through the first bidirectional power transmission terminal.

3. The energy storage system as described in claim 2, characterized in that, The data of the energy storage module includes: The real-time state of charge, real-time health, and input / output electrical parameters of the corresponding battery pack; and the input / output electrical parameters of the corresponding energy storage module.

4. The energy storage system as described in claim 3, characterized in that, The battery management of the battery pack of the energy storage module includes: The temperature parameters and input / output electrical parameters of the battery pack are sampled, and protection control is performed in real time according to the cell specifications and corresponding settings of the battery pack.

5. The energy storage system as described in claim 4, characterized in that, The sampling of the battery pack's temperature and input / output electrical parameters, and the real-time protection control based on the battery pack's cell specifications and corresponding settings, include: Obtain the cell specifications of the current battery pack to get the corresponding fault judgment threshold; When the temperature and / or input / output electrical parameters of the battery pack obtained from the sampling are used to determine whether the fault determination threshold has been reached, if the threshold is reached, it is determined to be a fault, and the first CNC bidirectional DC-DC converter unit is controlled to stop working; otherwise, the current state is maintained and no processing is performed. If the fault continues or worsens after the first CNC bidirectional DC-DC converter unit stops working, the first automatic power switch will be disconnected.

6. The energy storage system as described in claim 2, characterized in that, The step of cutting off or connecting the first automatic power switch based on the data from the energy storage module and the data from the first voltage detection unit includes: During discharge, if the voltage of the first charging / discharging interface is detected to be at a set value, or if the voltage difference between the output voltage of the second bidirectional power transmission terminal of the first CNC bidirectional DC-DC converter and the voltage of the first charging / discharging interface is less than or equal to a preset value, the first automatic power switch is controlled to connect. During charging, if the voltage of the first charging / discharging interface is detected to meet the input voltage of the first CNC bidirectional DC-DC converter, the first automatic power switch is controlled to connect.

7. The energy storage system as described in claim 1, characterized in that, The second control and management module includes: The system includes a second control and management unit, a human-machine interaction unit, a second voltage detection unit, a current detection unit, a semi-automatic power switch, and an energy transmission terminal for the energy storage module. The second control management unit is connected to the human-machine interaction unit, the data acquisition terminal of the current detection unit, the data acquisition terminal of the second voltage detection unit, and the control terminal of the semi-automatic power switch. The second control management unit is also connected to the first control management module of each energy storage module. One end of the semi-automatic power switch is connected to one end of the current detection unit. The other end of the current detection unit is connected to each energy storage module through the energy transmission terminal of the energy storage module and is connected to the first detection terminal of the second voltage detection unit. The other end of the semi-automatic power switch is connected to the second charging and discharging interface and is connected to the second detection terminal of the second voltage detection unit. The second control management unit is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the current detection unit, determine whether to cut off the semi-automatic power switch, and provide human-machine interaction through the human-machine interaction unit; during discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and allocates the output electrical parameters of each energy storage module in real time in combination with the discharging parameters of the second charging and discharging interface, and sends the allocation status as a control command to the first control management module of each energy storage module; during charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module.

8. The energy storage system as described in claim 7, characterized in that, The second control and management module also includes a second automatic power switch; The connection between one end of the semi-automatic power switch and one end of the current detection unit means that one end of the semi-automatic power switch is connected to one end of the current detection unit through a second automatic power switch. The control terminal of the second automatic power switch is connected to the second control management unit; The third detection terminal of the second voltage detection unit is connected to the end where the semi-automatic power switch is connected to the second automatic power switch; The second control and management unit is also used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the current detection unit, and to determine whether to cut off the second automatic power switch.

9. The energy storage system as described in claim 1, characterized in that, The second control and management module includes: The system includes a second control and management unit, a human-machine interaction unit, a second voltage detection unit, a second numerically controlled bidirectional DC-DC converter, a semi-automatic power switch, and an energy transmission terminal for the energy storage module. The second control management unit is connected to the human-machine interaction unit, the data acquisition terminal of the second voltage detection unit, the detection control terminal of the second CNC bidirectional DC-DC converter, and the control terminal of the semi-automatic power switch. The second control management unit is connected to the first control management module of each energy storage module. The first bidirectional power transmission terminal of the second CNC bidirectional DC-DC converter is connected to each energy storage module through the power transmission terminal of the energy storage module and is connected to the first detection terminal of the second voltage detection unit. The second bidirectional power transmission terminal of the second CNC bidirectional DC-DC converter is connected to one end of the semi-automatic power switch and to the third detection terminal of the second voltage detection unit. The other end of the semi-automatic power switch is connected to the second charging and discharging interface and to the second detection terminal of the second voltage detection unit. The second control management unit is used to detect and monitor the charging and discharging parameters of the second charging and discharging interface in real time through the second voltage detection unit and the second CNC bidirectional DC-DC converter, and to provide human-machine interaction through the human-machine interaction unit. During discharging, it acquires the target output electrical parameters and the data currently received from each energy storage module, and, in conjunction with the discharging parameters of the second charging and discharging interface, allocates the output electrical parameters of each energy storage module in real time, and sends the allocation status as a control command to the first control management module of each energy storage module. It also compares the input electrical parameters of the second CNC bidirectional DC-DC converter with the target output electrical parameters in real time, and adjusts the output electrical parameters of the second CNC bidirectional DC-DC converter to the target output electrical parameters. During charging, it allocates the input electrical parameters of each energy storage module in real time according to the charging parameters of the second charging and discharging interface and the data currently received from each energy storage module, and sends the allocation status as a control command to the first control management module of each energy storage module. At the same time, it acquires the charging parameters, and adjusts the output electrical parameters of the second CNC bidirectional DC-DC converter to the charging parameters in real time according to the input electrical parameters of the second CNC bidirectional DC-DC converter and the charging parameters.

10. A method for controlling the charging and discharging power of an energy storage system, applied to the energy storage system as described in any one of claims 1-9, characterized in that, The charging and discharging power control method of the energy storage system includes: During discharge: The second control and management module obtains the target output voltage and target output power based on the target output electrical parameters, and obtains data for each energy storage module, including at least the maximum output power, initial maximum energy storage capacity, real-time state of charge, and real-time health of each energy storage module. The target output power of each energy storage module is calculated based on the target output power, the maximum output power of each energy storage module, the initial maximum energy storage capacity, the real-time state of charge, and the real-time health status. The target output voltage and the target output power of each energy storage module are sent to the first control and management module of each corresponding energy storage module. After receiving the target output power and target output voltage of the module, the first control and management module of each energy storage module adjusts its own output electrical parameters to the target output power and target output voltage of the module, and each energy storage module operates in the discharge state. During charging: The second control and management module sends a charging command to the first control and management module of each energy storage module. If the current state of each energy storage module meets the charging conditions, it will operate in the charging state. Acquire data for each energy storage module, including at least the maximum input power, initial maximum energy storage capacity, and real-time health status of each energy storage module; The maximum power allocation value of each energy storage module is calculated based on the total maximum input power, the maximum input power of each energy storage module, the initial maximum energy storage capacity, and the real-time health status. When each energy storage module is in charging mode, its own charging power gradually increases from the preset safety parameter, and during the increase, the input power of each energy storage module is always less than or equal to the maximum power allocation value.

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