CN220822638U - Balanced control device and related system - Google Patents

Abstract

The utility model discloses an equalization control device and a related system, wherein the equalization control device comprises a power interface, a first serial interface, a first equalization interface and a control module; the control module obtains state parameters of a plurality of series battery packs, determines whether the plurality of series battery packs need to be balanced according to the state parameters of the plurality of series battery packs, and controls the first series interface to be connected with the power interface when the plurality of series battery packs do not need to be balanced, so that the energy storage converter (PCS) is connected with the plurality of series battery packs in series, and controls the corresponding first balanced interface to be connected with the power interface when at least one battery pack needs to be balanced, so that the energy storage converter is only connected with the battery pack needing to be balanced, thereby providing larger charge and discharge power through the energy storage converter, further providing larger charge and discharge balanced current for the battery pack needing to be balanced, further improving the balanced efficiency of the energy storage system, shortening the balanced period and reducing the balanced cost.

Description

Balanced control device and related system

Technical Field

The utility model relates to the technical field of energy storage systems, in particular to an equalization control device and a related system.

Background

The energy storage system is a battery cluster formed by connecting a plurality of battery packs in series. Because certain differences exist among the voltages or the SOCs (State Of Charge) Of different battery packs under the influence Of factors such as production process, storage time and the like, the larger the differences among the voltage differences or the SOCs Of the different battery packs are, the larger the influence on the available energy storage capacity and performance Of the energy storage system is; therefore, when the voltage difference or the SOC difference between the different battery packs is large, it is necessary to equalize each battery pack in the energy storage system. However, in the equalization of the energy storage system at present, there is a great improvement space in terms of equalization efficiency, equalization operation convenience and cost of an equalization device.

Disclosure of utility model

The utility model discloses an equalization control device and a related system, which are used for improving the equalization rate of an energy storage system, reducing the equalization cost and improving the operation convenience.

In a first aspect, the present utility model discloses an equalization control device applied to an energy storage system, the energy storage system including a plurality of battery packs connected in series, the equalization control device comprising: the power interface is used for being connected with the energy storage converter; a first serial interface for connecting with the plurality of battery packs in series; the first equalization interfaces are used for being connected with one battery pack, and the first equalization interfaces are used for being respectively and correspondingly connected with the battery packs; the control module is used for acquiring parameters of the plurality of battery packs, determining whether the plurality of battery packs need to be balanced according to the parameters of the plurality of battery packs, controlling the first serial interface to be connected with the power interface when the plurality of battery packs do not need to be balanced, and sending charge and discharge parameters of the plurality of battery packs to the energy storage converter so as to enable the energy storage converter to charge and discharge the plurality of battery packs; when at least one battery pack needs to be balanced, controlling the first balancing interface correspondingly connected with the battery pack to be connected with the power interface; and sending the charge and discharge parameters of the battery pack to be balanced to the energy storage converter so that the energy storage converter charges and discharges the battery pack to be balanced.

In some optional examples, the equalization control device further comprises a switch; the first end of the change-over switch is connected with the power interface, the second end of the change-over switch is connected with the first serial interface, and the third end of the change-over switch is connected with the at least one first equalizing interface; the control module is connected with the control end of the change-over switch; the control module is further used for controlling the first end and the second end of the change-over switch to be connected when the plurality of battery packs do not need to be balanced; and when at least one battery pack needs to be balanced, controlling the first end of the change-over switch to be connected with the third end.

In some optional examples, the equalization control device further comprises a plurality of equalization switches; the first ends of the equalization switches are connected with the third ends of the change-over switches, and the second ends of the equalization switches are correspondingly connected with the first equalization interfaces respectively; the control module is respectively connected with the control ends of the equalization switches, and is further used for controlling the first ends of the equalization switches correspondingly connected with the control module to be connected with the second ends of the equalization switches when at least one battery pack needs equalization.

In some alternative examples, the equalization control device further includes a first communication interface; the first communication interface is in communication connection with the plurality of battery packs, and is also connected with the control module; the first communication interface is used for receiving parameters sent by the plurality of battery packs and transmitting the parameters to the control module.

In some optional examples, the control module is further configured to send a connect instruction and a disconnect instruction to the energy storage converter; the communication instruction is used for enabling the energy storage converter to be communicated with the power interface, and the disconnection instruction is used for enabling the energy storage converter to be disconnected with the power interface.

In some alternative examples, the equalization control device further comprises a second communication interface; the second communication interface is used for being in communication connection with the energy storage converter; the control module is further connected with the second communication interface, and is further used for sending a connection instruction, a disconnection instruction and charge and discharge parameters of the battery pack to the energy storage converter through the second communication interface.

In some optional examples, the equalization control device further comprises an operation panel; the control module is further used for sending equalization prompt information through the operation panel to prompt a user that at least one battery pack in the energy storage system needs equalization, receiving equalization instructions input by the user through the operation panel, and controlling at least one corresponding first equalization interface to be connected with the power interface according to the equalization instructions.

In some alternative examples, the battery pack includes a second serial interface and a second equalization interface, the second serial interface being connected in parallel with the second equalization interface, the second serial interface being for connection with the second serial interface of the first serial interface or other battery packs, the second equalization interface being for connection with the first equalization interface.

In a second aspect, the utility model discloses an equalization control system applied to an energy storage system, comprising an energy storage converter and an energy storage management unit, wherein the energy storage management unit comprises the equalization control device according to any one of the above.

In some alternative examples, the operating voltage range of the energy storage converter covers the voltage range of one or more series battery packs in the energy storage system and is capable of charging and discharging the one or more series battery packs on command.

In a third aspect, an energy storage system is disclosed that includes a plurality of battery packs in series and an equalization control system as described above.

The utility model discloses an equalization control device and a related system, wherein an energy storage system comprises a plurality of battery packs connected in series, the equalization control device comprises a power interface, a first serial interface, a first equalization interface and a control module, the control module acquires state parameters of the plurality of battery packs, determines whether the plurality of battery packs need to be equalized according to the state parameters of the plurality of battery packs, controls the first serial interface to be connected with the power interface when the plurality of battery packs do not need to be equalized, and sends charge and discharge parameters of the plurality of battery packs to an energy storage converter so as to enable the energy storage converter to charge and discharge the plurality of battery packs, and on one hand, when at least one battery pack needs to be equalized, controls the first equalization interface correspondingly connected with the energy storage converter to be connected with the power interface, and sends the charge and discharge parameters of the battery packs needing to be equalized to the energy storage converter so as to enable the energy storage converter to charge and discharge the battery packs needing to be equalized, thereby larger charge and discharge equalization currents can be provided for the battery packs needing to be equalized through the energy storage converter, and the equalization current can be further improved, and the equalization period of the energy storage system can be shortened; on the one hand, no additional equalization equipment is needed, and equalization is realized by using the existing energy storage converter of the energy storage system, so that the equalization cost of the energy storage system is reduced. In addition, the balance of the energy storage system can be conveniently and rapidly realized by controlling the power interface to be connected with the first balance interface, so that the balance of the energy storage system can be automatically completed without manual intervention, and the balance convenience of the energy storage system is greatly improved.

Drawings

In order to more clearly describe the embodiments of the present utility model or the technical solutions in the background art, the following description will describe the drawings that are required to be used in the embodiments of the present utility model or the background art.

Fig. 1 is a schematic diagram of a connection relationship between an equalization control device with a first equalization interface and an energy storage converter and a battery pack according to an embodiment of the present utility model.

Fig. 2 is a schematic diagram of connection relationship between an energy storage converter and a battery pack and another equalization control device with multiple first equalization interfaces according to an embodiment of the present utility model.

Fig. 3 is a schematic structural diagram of another equalization control device with a change-over switch according to an embodiment of the present utility model.

Fig. 4 is a schematic structural diagram of another equalization control device with a change-over switch and an equalization switch according to an embodiment of the present utility model.

Fig. 5 is a schematic diagram of connection relationship between an energy storage converter and a battery pack and another equalization control device with a first communication interface according to an embodiment of the present utility model.

Fig. 6 is a schematic diagram of a connection relationship between an equalization control device with a second communication interface and an energy storage converter according to an embodiment of the present utility model.

Fig. 7 is a schematic diagram of a connection relationship between an equalization control device with an operation panel and an energy storage converter according to an embodiment of the present utility model.

Fig. 8 is a schematic structural view of a battery pack according to an embodiment of the present utility model.

Fig. 9 is a schematic diagram of a connection relationship between an energy storage converter and an equalization control device and a battery pack according to an embodiment of the present utility model.

Fig. 10 is a schematic diagram illustrating a connection relationship between another equalization control device and a battery pack and an energy storage converter with a second equalization interface according to an embodiment of the present utility model.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The battery pack is generally composed of a plurality of battery cells connected in series, and the battery cells can be lithium iron phosphate battery cells or sodium battery cells and the like. The voltage of a single battery pack is typically not too high, such as typically not exceeding 120V, due to the weight of the battery pack and the management chip. If higher output power and efficiency are desired, it is desirable to boost the voltage of an energy storage system comprising a plurality of series-connected battery packs and reduce the current of the energy storage system.

Since the battery packs are individually produced, stored, and transported, there is a difference in voltage or SOC of the different battery packs under the influence of factors such as a production process, a storage time, and a transport time. Based on this, during the process of assembling the energy storage system, it is necessary to equalize each battery pack in the energy storage system, so as to reduce the voltage difference or SOC difference of each battery pack in the energy storage system.

In addition, since there may be a difference in the discharge parameters of different battery packs, there may be a difference in the voltage or SOC of different battery packs after the energy storage system is operated for a period of time. Based on this, during operation of the energy storage system, it is also necessary to equalize each battery pack in the energy storage system.

Again, if a certain battery pack in the energy storage system fails, after the battery pack is maintained or replaced, the voltage or SOC of the maintained or replaced battery pack will also be different from that of other battery packs. Based on this, during maintenance of the energy storage system, it is also necessary to balance the individual battery packs in the energy storage system.

Although each battery pack in the energy storage system can be connected in series after being filled or emptied through special equipment during the assembly or maintenance of the energy storage system, the battery packs in the energy storage system cannot be balanced during the operation of the energy storage system. Moreover, the balancing in the mode can lead to lower balancing efficiency, longer balancing period and higher balancing cost.

Although the energy of the high-voltage or high-SOC battery pack can be transferred to the low-voltage or low-SOC battery pack through the energy storage inductor during operation of the energy storage system, the balancing of the individual battery packs in the energy storage system is performed. However, during the assembly or maintenance of the energy storage system, the battery packs in the energy storage system cannot be balanced in this way, or the balanced power in this way is smaller, the balanced efficiency is lower, and the requirement of the assembly or maintenance of the energy storage system cannot be met.

Based on the above, the utility model discloses an equalization control device of an energy storage system, which is used for equalizing the energy storage system in the process of assembling, working or maintaining the energy storage system, when the battery packs in the energy storage system need to be equalized, the equalization control device controls the battery packs which need to be equalized to be connected with an energy storage converter (Power Conversion System, PCS for short), when the battery packs in the energy storage system do not need to be equalized, all the battery packs in the energy storage system are controlled to be connected with the energy storage converter together in series, so that the energy storage converter which is used for working and supplying power to the energy storage system can be multiplexed into an equalization power supply which is used for equalizing and supplying power to the energy storage system, and the equalization efficiency of the energy storage system can be improved through the energy storage converter with larger power and the equalization cost can be reduced; because the balancing device can automatically complete the balancing task without manual intervention, the balancing maintenance of the energy storage system is simple and convenient.

As an optional implementation of the disclosure, an embodiment of the present utility model discloses an equalization control device, which is applied to an energy storage system, and the equalization control device may perform equalization on the energy storage system during an assembly, a work or a maintenance process of the energy storage system.

As shown in fig. 1, the energy storage system 10 includes a plurality of battery packs 100 connected in series, and the equalization control device 20 includes a power interface 201, a first serial interface 202, at least one first equalization interface 203, and a control module 204. It will be appreciated that fig. 1 illustrates only 3 battery packs 100, and is not limited thereto, and that the battery packs 100 of the energy storage system 10 may be 2, 4, 5, or more.

The power interface 201 is used to connect to the energy storage converter 30. The power interface 201 may be a PCS interface, and the energy storage converter 30 may be connected to a power grid or a photovoltaic power plant, etc. for controlling the energy storage system 10 to charge and discharge. For example, in the case where the power of the plurality of battery packs 100 is consumed, the plurality of battery packs 100 may be charged by the energy storage converter 30; or in the case where the plurality of battery packs 100 are overfilled, the plurality of battery packs 100 may be discharged through the energy storage converter 30.

The first serial interface 202 is for connecting to a plurality of battery packs 100 in series. For example, each battery pack 100 includes a positive electrode and a negative electrode, and among the plurality of battery packs 100 connected in series, the positive electrode of the first battery pack 100 is connected to the negative electrode of the second battery pack 100, the positive electrode of the second battery pack 100 is connected to the negative electrode of the third battery pack 100, and so on, and then the negative electrode of the first battery pack 100 is connected to the second negative electrode of the first serial interface 202, and the positive electrode of the last battery pack 100 is connected to the second positive electrode of the first serial interface 202. Among them, the different battery packs 100 and the battery pack 100 and the first serial interface 202 may be connected in series by a wire or the like.

One first equalization interface 203 is configured to be connected to one battery pack 100, and a plurality of first equalization interfaces 203 are configured to be respectively and correspondingly connected to a plurality of battery packs 100. Specifically, the second positive terminal of the first equalization interface 203 is connected to the positive electrode of the battery pack 100, and the second negative terminal of the first equalization interface 203 is connected to the negative electrode of the battery pack 100.

The control module 204 is configured to obtain parameters of the plurality of battery packs 100 in the energy storage system 10, determine whether the plurality of battery packs 100 need to be balanced according to the parameters of the plurality of battery packs 100, and control the first serial interface 202 to be connected with the power interface 201 when the plurality of battery packs 100 do not need to be balanced, and send charge and discharge parameters of the plurality of battery packs 100 to the energy storage converter 30, so that the energy storage converter 30 charges and discharges the plurality of battery packs 100. When at least one battery pack 100 needs to be balanced, controlling at least one corresponding first balancing interface 203 to be connected with the power interface 201; that is, at least one first balancing interface 203 connected to at least one battery pack 100 to be balanced is controlled to be connected to the power interface 201, and charge and discharge parameters of the battery pack 100 to be balanced are transmitted to the energy storage converter 30, so that the energy storage converter 30 charges and discharges the battery pack 100 to be balanced.

Parameters of the battery pack 100 may include one or more of voltage, current, SOC, and temperature, among others. For example, if the parameters of the battery pack 100 include voltages, the battery pack 100 may be voltage-equalized according to the parameters; if the parameters of the battery pack 100 include SOC, the battery pack 100 may be subjected to electric quantity equalization according to the parameters; if the parameters of the battery pack 100 include voltage and SOC, the battery pack 100 may be voltage-balanced and charge-balanced according to the parameters. The charge and discharge parameters of the battery pack 100 include a charge and discharge current, a charge and discharge voltage, a target current, and the like of the battery pack 100. After the charge and discharge parameters of the plurality of battery packs 100 or the battery packs 100 to be balanced are sent to the energy storage converter 30, the energy storage converter 30 can be enabled to provide charge and discharge currents matched with the plurality of battery packs 100 or the battery packs 100 to be balanced, and the like.

During assembly, operation, or maintenance of the energy storage system 10, the control module 204 obtains and stores parameters such as the voltage and SOC of the plurality of battery packs 100 in the energy storage system 10 and compares the voltage and/or SOC of any two battery packs 100. If the voltage difference and/or the SOC difference between any two battery packs 100 is smaller than the preset value, it is indicated that the plurality of battery packs 100 in the energy storage system 10 do not need to be balanced, and at this time, the control module 204 may control the first serial interface 202 to be connected to the power interface 201, and send the charge and discharge parameters of the plurality of battery packs 100 to the energy storage converter 30, so that the plurality of battery packs 100 connected in series in the energy storage system 10 are connected to the energy storage converter 30, and the plurality of battery packs 100 connected in series are charged or discharged through the energy storage converter 30.

If the voltage difference and/or the SOC difference of the at least two battery packs 100 is greater than or equal to a preset value, for example, the voltage difference is greater than or equal to 0.1v×n and/or the SOC difference is greater than or equal to 5%, N is the number of battery packs 100 in the energy storage system, which indicates that the voltage difference and/or the SOC difference of the at least two battery packs 100 is greater, it is necessary to equalize at least one battery pack 100 so that the voltage difference and/or the SOC difference of the at least two battery packs 100 is less than the preset value, for example, the voltage difference is less than 0.1v×n and/or the SOC difference is less than 5%, where the preset value of the voltage difference and the preset value of the SOC difference are not the same. At this time, the control module 204 may control the first equalization interface 203 connected to the battery pack 100 to be equalized to be connected to the power interface 201, and send the charge and discharge parameters of the battery pack 100 to be equalized to the energy storage converter 30, so that the battery pack 100 to be equalized is connected to the energy storage converter 30, and the battery pack 100 to be equalized is charged or discharged through the energy storage converter 30.

It can be appreciated that after all the battery packs 100 in the energy storage system 10 are balanced, the voltage difference and/or the SOC difference between any two battery packs 100 is less than the preset value, and the control module 204 may control the first serial interface 202 to connect with the power interface 201, so that the energy storage system 10 performs the conventional charge and discharge operation.

It may be further understood that the control module 204 may set a balanced target voltage and/or a target SOC, a balanced current value, and the like according to the stored parameters such as the voltages and/or the SOCs of the plurality of battery packs 100, and then compare the voltage of the battery pack 100 to be balanced with the target voltage, and/or compare the SOC of the battery pack 100 to be balanced with the target SOC, and if the voltage of the battery pack 100 to be balanced is greater than the target voltage, and/or if the SOC of the battery pack 100 to be balanced is greater than the target SOC, control the battery pack 100 to discharge to implement the balancing of the battery pack 100; if the voltage of the battery pack 100 to be balanced is less than the target voltage and/or the SOC of the battery pack 100 to be balanced is less than the target SOC, the battery pack 100 is controlled to be charged to achieve the balance of the battery pack 100.

In addition, during the balancing process of the battery pack 100, the control module 204 may periodically collect parameters such as the voltage and the SOC of the battery pack 100, compare the collected voltage with the target voltage, and/or compare the collected SOC with the target SOC, and if the difference between the collected voltage and the target voltage is smaller than the preset value, and/or the difference between the collected SOC and the target SOC is also smaller than the preset value, which indicates that the balancing of the battery pack 100 is completed, the control module 204 controls the battery pack 100 to stop charging or discharging by controlling the connection of the first serial interface 202 and the power interface 201, i.e. controls the battery pack 100 to stop balancing.

Based on this, the energy storage converter 30 that supplies power to the energy storage system 10 can be multiplexed into an equalizing power supply that supplies power to the energy storage system 10 in an equalizing manner, so that charging and discharging power with larger power can be provided by the energy storage converter 30, and further equalizing efficiency of the energy storage system 10 can be improved, equalizing period of the energy storage system 10 can be shortened, and equalizing cost of the energy storage system 10 can be reduced. In addition, the balance of the energy storage system 10 can be conveniently and rapidly realized by connecting the control power interface 201 with the first balance interface 203, and the balance efficiency of the energy storage system 10 is further improved.

It should be noted that the equalization control device may be integrated in an energy storage management unit (EMU) of the energy storage system, or the equalization control device may multiplex the energy storage management unit (EMU); the control module 204 may be integrated in an energy controller (EMS) of the energy storage management unit (EMU) or may be multiplexed.

In some embodiments of the present utility model, as shown in fig. 1, the equalization control device 20 may include only one first equalization interface 203. When equalization is required for one battery pack 100, the first equalization interface 203 connected to the power interface 201 may be connected to the one battery pack 100 to achieve equalization for the one battery pack 100. When the plurality of battery packs 100 need to be balanced, the first balancing interface 203 connected to the power interface 201 may be sequentially connected to the plurality of battery packs 100 to sequentially realize the balancing of the plurality of battery packs 100.

Of course, the present utility model is not limited thereto, and in other embodiments, as shown in fig. 2, the equalization control device 20 may include a plurality of first equalization interfaces 203, and the plurality of first equalization interfaces 203 are respectively connected to the plurality of battery packs 100. When any battery pack 100 needs to be balanced, the power interface 201 and the first balancing interface 203 connected with the battery pack 100 can be connected to realize the balancing of the battery pack 100.

In some embodiments of the present utility model, as shown in fig. 3, the equalization control device 20 further includes a switch 205. A first terminal of the switch 205 is connected to the power interface 201, a second terminal of the switch 205 is connected to the first serial interface 202, and a third terminal of the switch 205 is connected to the at least one first equalization interface 203. The control module 204 is connected to the control end of the switch 205, and the control module 204 is further configured to control the first end of the switch 205 to be connected to the second end to control the power interface 201 to be connected to the first serial interface 202 when no equalization is required for the plurality of battery packs 100, and control the first end of the switch 205 to be connected to the third end to control the power interface 201 to be connected to the corresponding at least one first equalization interface 203 when at least one battery pack 100 is required to be equalized.

Wherein, the first end of the switch 205 includes a first positive end a1 and a first negative end b1, the second end of the switch 205 includes a second positive end a2 and a second negative end b2, and the third end of the switch 205 includes a third positive end a3 and a third negative end b3. The first positive terminal a1 may be connected to the second positive terminal a2 or the third positive terminal a3, and the first negative terminal b1 may be connected to the second negative terminal b2 or the third negative terminal b3. The connection of the first end and the second end means that the first positive end a1 is connected with the second positive end a2, the first negative end b1 is connected with the second negative end b2, the connection of the first end and the third end means that the first positive end a1 is connected with the third positive end a3, and the first negative end b1 is connected with the third negative end b3.

In addition, a second positive terminal a2 of the switch 205 is connected to the first positive terminal of the first serial interface 202, and a second negative terminal b2 of the switch 205 is connected to the first negative terminal of the first serial interface 202; the third positive terminal a3 of the switch 205 is connected to the first positive terminal of the first equalization interface 203 and the second negative terminal b3 of the switch 205 is connected to the first negative terminal of the first equalization interface 203.

In some embodiments, as shown in fig. 3, a change-over switch 205 may include a double pole double throw switch, which may include a relay 2050, and the control module 204 may control the current of the relay 2050, etc. through a driving circuit, to control the relay 2050 to engage or disengage the double pole, and thus to control the double pole double throw switch to be closed or opened.

It can be appreciated that the control module 204 can determine whether the current state of the switch 205 is closed or open according to a driving signal of the driving circuit, and the like, and further determine whether to perform equalization according to the state information of the switch 205. Of course, the present utility model is not limited thereto, and in other embodiments, one switch 205 may further include two single pole double throw switches or two MOS switches, etc., which are not described herein.

For example, when at least one battery pack 100 needs to be balanced, the control module 204 controls the first end of the switch 205 to be connected to the third end so as to control the power interface 201 to be connected to the corresponding at least one first balancing interface 203, and then the control module 204 detects the state of the switch 205, and if it is detected that the first end of the switch 205 is connected to the third end, the control module 204 performs the subsequent balancing steps of setting the balanced target voltage and/or the balanced target SOC; if it is not detected that the first terminal of the switch 205 is connected to the third terminal, the control module 204 continues to detect the state of the switch 205 until it detects that the first terminal of the switch 205 is connected to the third terminal, and then the subsequent equalization step is performed.

After the equalization of the battery packs 100 is completed, that is, when all the battery packs 100 in the energy storage system 10 do not need equalization, the control module 204 controls the first end of the switch 205 to be connected with the third end so as to control the power interface 201 to be connected with the corresponding at least one first equalization interface 203, then the control module 204 detects the state of the switch 205, if the first end of the switch 205 is not detected to be connected with the third end, the control module 204 continuously detects the state of the switch 205 until the first end of the switch 205 is detected to be connected with the third end, and the control module 204 controls the energy storage converter 30 to be connected with the power interface 201.

In some embodiments, as shown in fig. 3, the equalization control device 20 only includes one first equalization interface 203, and the equalization control device 20 only includes a switch 205. However, in other embodiments, as shown in fig. 4, the equalization control device 20 includes a plurality of first equalization interfaces 203, and then the equalization control device 20 may further include a plurality of equalization switches 206, where a first end of each of the equalization switches 206 is connected to a third end of the switch 205, a second end of each of the plurality of equalization switches 206 is respectively connected to a plurality of first equalization interfaces 203, the control module 204 is respectively connected to a control end of each of the plurality of equalization switches 206, and the control module 204 is further configured to control, when at least one battery pack 100 needs to be equalized, the corresponding first end of at least one equalization switch 206 to be connected to the second end thereof.

Wherein the first end of the equalization switch 206 includes a first positive end c1 and a first negative end d1, and the second end of the equalization switch 206 includes a second positive end c2 and a second negative end d2. The connection of the first terminal of the equalizing switch 206 to the second terminal thereof means that the first positive terminal c1 is connected to the second positive terminal c2 and the first negative terminal d1 is connected to the second negative terminal d2.

In some embodiments, as shown in fig. 4, an equalization switch 206 may comprise a double pole single throw switch, which may also include a relay 2060, and the control module 204 may control the closing and opening of the double pole by controlling the relay 2060. Of course, the utility model is not limited thereto, and in other embodiments, one equalization switch 206 may also include two single pole single throw switches or two MOS switches, etc.

Of course, the present utility model is not limited thereto, and in other embodiments, the control module 204 may be a chip, etc., where the power interface 201, the first serial interface 202 and the at least one first equalization interface 203 are connected to different pins of the chip, and the control module may implement connection between the power interface 201 and the first serial interface 202 or the first equalization interface 203 through a circuit inside the chip, or may implement communication connection with the battery pack 100 and/or the energy storage converter 30 through a wireless communication module inside the control module.

If the equalization control device 20 includes only one first equalization interface 203, the first equalization interface 203 may be manually controlled to sequentially connect to the plurality of battery packs 100. If the equalization control device 20 includes a plurality of first equalization interfaces 203, the plurality of first equalization interfaces 203 may be automatically controlled by the control module 204 to connect to the plurality of battery packs 100.

In some embodiments of the present utility model, as shown in fig. 5, the equalization control device 20 may further include a first communication interface 207, where the first communication interface 207 is communicatively connected to the plurality of battery packs 100, and the first communication interface 207 is further connected to the control module 204. The first communication interface 207 is configured to receive parameters sent by the plurality of battery packs 100, and transmit the parameters to the control module 204.

The first communication interface 207 may be connected to the battery pack 100 through a communication line in a wired communication manner, or may be connected to the battery pack 100 through a wireless communication manner such as 4G, bluetooth, WIFI, etc. Also, the first communication interface 207 may be a BMS communication interface to be communicatively connected with the battery management system BMS in the battery pack 100.

It should be understood that fig. 5 and the following figures only illustrate an example of the equalization control device 20 having one first equalization interface 203, but the invention is not limited thereto, i.e. the equalization control device 20 having a plurality of first equalization interfaces 203 may also have the first communication interfaces 207, etc.

In some embodiments of the present utility model, the control module 204 is further configured to send a connect command and a disconnect command to the energy storage converter 30; the connect command is used to connect the energy storage converter 30 to the power interface 201, and the disconnect command is used to disconnect the energy storage converter 30 from the power interface 201. Of course, the present utility model is not limited thereto, and in other embodiments, the control module 204 may also control the connection or disconnection of the energy storage converter 30 and the power interface 201 by controlling the switch between the energy storage converter 30 and the power interface 201, which is not described herein.

In some embodiments, as shown in fig. 6, the equalization control device 20 may further include a second communication interface 208, where the second communication interface 208 is configured to communicatively connect with the energy storage converter 30. The second communication interface 208 may be a PCS communication interface. The control module 204 is further connected to the second communication interface 208, and the control module 204 is further configured to send a connection instruction, a disconnection instruction, a charging and discharging parameter of the battery pack 100, and the like to the energy storage converter 30 through the second communication interface 208.

For example, if at least one battery pack 100 needs to be balanced, the control module 204 sends a disconnection instruction to the energy storage converter 30 through the second communication interface 208, so that the energy storage converter 30 is disconnected from the power interface 201, then the control module 204 controls the first balancing interface 203 connected to the battery pack 100 to be balanced to be connected to the power interface 201 by controlling the state of the switch 205, and then the control module 204 sends a connection instruction to the energy storage converter 30 through the second communication interface 208, so that the energy storage converter 30 is connected to the battery pack 100 to be balanced.

After the equalization of the battery pack 100 is completed, the control module 204 sends a disconnection instruction to the energy storage converter 30 through the second communication interface 208, so that the energy storage converter 30 is disconnected from the power interface 201, then the control module 204 controls the state of the switch 205 to control the first serial interface 202 to be connected with the power interface 201, and then the control module 204 sends a connection instruction to the energy storage converter 30 through the second communication interface 208, so that the energy storage converter 30 is connected with the plurality of battery packs 100 connected in series in the energy storage system 10.

It can be appreciated that when the energy storage converter 30 supplies power to the plurality of battery packs 100 connected in series, the power supply voltage is relatively high, and when the energy storage converter 30 supplies power to the portion of the battery packs 100 to be balanced, the power supply voltage is relatively low, so before the control module 204 controls the first balancing interface 203 to be connected to the power interface 201, and before the control module 204 controls the first serial interface 202 to be connected to the power interface 201, the energy storage converter 30 is controlled to be disconnected from the power interface 201, so as to avoid that a large current caused by voltage change passes through the switch 205, and the switch 205 is damaged.

In some embodiments of the present utility model, as shown in fig. 7, the equalization control device 20 further includes an operation panel 209, where the operation panel 209 is connected to the control module 204, and the control module 204 is further configured to send equalization prompt information through the operation panel 209 to prompt a user that at least one battery pack 100 in the energy storage system 10 needs to be equalized, and receive an equalization instruction input by the user through the operation panel 209, so as to control the corresponding at least one first equalization interface 203 to be connected to the power interface 201 according to the equalization instruction. Of course, the operation panel 209 may also send out other information, such as a power alarm information, etc., and the operation panel 209 may also receive other instructions input by the user, such as a stop charging or start charging instruction, etc.

After the control module 204 determines that at least one battery pack 100 in the energy storage system 10 needs to be balanced, an equalization prompt message is sent to a user through the operation panel 209, and after the user inputs an equalization instruction through the operation panel 209, the control module 204 controls the corresponding at least one first equalization interface 203 to be connected with the power interface 201 through the change-over switch 205 and the like.

It should be noted that, if the first equalization interface 203 needs to be connected with the plurality of battery packs 100 in sequence by manual control, after receiving the equalization prompt information, the user may control the first equalization interface 203 to be connected with one battery pack 100 to be equalized, which is prompted by the equalization prompt information, and may also control the first equalization interface 203 to be connected with the plurality of battery packs 100 to be equalized, which is prompted by the equalization prompt information, in sequence.

In some embodiments, the operation panel 209 may include a display panel and keys to display equalization prompt information and the like through the display panel, input equalization instructions through the keys, and the like. Of course, the present utility model is not limited thereto, and in other embodiments, the operation panel 209 may further include a touch display panel to display information and input instructions through the touch display panel.

Of course, the present utility model is not limited thereto, and in other embodiments, the equalization control device 20 may not include the operation panel 209, that is, the equalization control device 20 need not send equalization prompt information to the user, and need not perform equalization based on the equalization instruction input by the user, but may automatically control the battery pack 100 to perform equalization after determining that the battery pack 100 needs to be equalized.

In some embodiments of the present utility model, as shown in fig. 8, the battery pack 100 may include a series cell group 101, a battery management system BMS, a third communication interface 102, a second series interface 103, a second equalization interface 104, and a sampling unit 105.

Wherein the series cell group 101 includes a plurality of battery cells or battery cell groups connected in series. The positive electrode of the series cell stack 101 may be connected to the positive electrode of the first battery cell or battery cell stack of the series battery cells or battery cell stacks, and the negative electrode of the series cell stack 101 may be connected to the negative electrode of the last battery cell or battery cell stack of the series battery cells or battery cell stacks. The positive electrode of the series cell group 101 may be connected to the positive electrode of the battery pack 100, and the negative electrode of the series cell group 101 may be connected to the negative electrode of the battery pack 100.

The first positive terminal e1 of the second serial interface 103 and the first positive terminal f1 of the second equalization interface 104 are both connected with the positive electrode of the serial cell group 101, and the first negative terminal e2 of the second serial interface 103 and the first negative terminal f2 of the second equalization interface 104 are connected with the negative electrode of the serial cell group 101 through the sampling unit 105. That is, the second serial interface 103 is connected in parallel with the second equalization interface 104.

The sampling unit 105 is further connected to the battery management system BMS, and the sampling unit 105 is configured to collect charge and discharge currents of each battery cell or battery cell group of the series battery cell group 101 and send the charge and discharge currents to the battery management system BMS, so that the battery management system BMS calculates the SOC of the battery pack 100 according to the charge and discharge currents.

The battery management system BMS may also be directly connected to the series cell group 101 for collecting voltage and temperature of the series cell group 101, etc. The battery management system BMS may also be connected to the third communication interface 102.

As shown in fig. 9, the battery management system BMS may be connected to the control module 204 through the third communication interface 102 and the first communication interface 207 to transmit parameters such as SOC, voltage, and temperature to the control module 204. The third communication interface 102 is also a BMS communication interface.

The second serial interface 103 is configured to connect to the first serial interface 202 or the second serial interface 103 of another battery pack 100. For example, the second positive terminal e3 of the second serial interface 103 is connected to the second positive terminal of the first serial interface 202, the second negative terminal e4 of the second serial interface 103 is connected to the second positive terminal of the other second serial interface 103, and the second negative terminal of the other second serial interface 103 is connected to the second negative terminal of the first serial interface 202, so as to realize serial connection of the plurality of battery packs 100 and the first serial interface 202.

The second equalization interface 104 is configured to be coupled to the first equalization interface 203. For example, a second positive terminal of the second balanced interface 104 is connected to a second positive terminal of the first balanced interface 203, and a second negative terminal of the second balanced interface 104 is connected to a second negative terminal of the first balanced interface 203. It will be appreciated that the first positive terminal is connected to the second positive terminal and the first negative terminal is connected to the second negative terminal of the same interface, so that the transmission of signals within the same interface is achieved.

It should be noted that, in other embodiments, if the equalization control device 20 includes only one first equalization interface 203, the battery pack 100 may include only the second serial interface 103, and not include the second equalization interface 104, or the second serial interface 103 may be multiplexed into the second equalization interface 104 to be electrically connected with the first equalization interface 203.

In some embodiments of the present utility model, as shown in fig. 10, the control module 204 may include an MCU (Microcontroller Unit, micro control unit), and the equalization control device 20 may further include a DC-DC circuit, where the DC-DC circuit is connected to the power interface 201, and is configured to DC-DC convert a direct current output by the power interface 201 and provide the direct current to the MCU.

It should be noted that, although the switch 205 may switch between the first serial interface 202 and the first equalization interface 203, the switching speed is fast, so that the MCU is not powered down and restarted, and thus the normal operation of the control module 204 is not affected.

The power interface 201 may include a PCS power electrode, and the first serial interface 202 and the first equalization interface 203 may include Pack power electrodes. The PCS power electrode and Pack power electrode both include a positive electrode 1 and a negative electrode 2. Wherein the positive electrode 1 may be a first positive terminal or a second positive terminal, and the negative electrode 2 may be a first negative terminal or a second negative terminal.

The first communication interface 207 may include a 485 circuit, i.e., a remote weighing data acquisition method circuit of the communication interface, and the second communication interface 208 may include a CAN (Controller Area Network, controller area network bus) circuit, and the operation panel 209 includes an LCD (liquid CRYSTAL DISPLAY) circuit.

The second serial interface 103 includes a power positive pole and a power negative pole, and the second equalization interface 104 may include an equalization receptacle, which may be a foolproof aviation receptacle, connected in parallel between the power positive pole and the power negative pole. The AFE is used to detect the voltage, temperature, and current of each cell or group of cells of the series stack 101. The AFE (Analog Front End) and the resistor R constitute a sampling unit 105. The AFE and the MCU communicate and collect the voltage, temperature and current of each battery cell or battery cell group in the series cell group 101, and calculate the SOC and the like. The AFE and the MCU constitute the BMS.

Of course, the present utility model is not limited to this, and in practical application, the structure of the battery pack may be different, and the structures of the second serial interface 103, the second equalization interface 104, the BMS, etc. inside the battery pack may also be different, and the structures of the equalization control device may also be different, which will not be described herein.

As another optional implementation of the disclosure, an embodiment of the present utility model discloses an equalization control system, as shown in fig. 1 and fig. 2, where the equalization control system includes an energy storage converter 30 and an energy storage management unit, and the energy storage management unit includes the equalization control device 20 disclosed in any of the foregoing embodiments.

The operating voltage range of the energy storage converter 30 covers the voltage range of one or more battery packs 100 connected in series in the energy storage system, and can charge and discharge the one or more battery packs 100 connected in series according to the instruction.

As another alternative implementation of the present disclosure, an embodiment of the present disclosure discloses an energy storage system comprising a plurality of battery packs in series and an equalization control system as described above.

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples only represent a few embodiments of the present specification, which are described in more detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the present description, which is within the scope of the present description. Accordingly, the protection scope of the patent should be determined by the appended claims.

Claims (10)

1. An equalization control device for an energy storage system comprising a plurality of battery packs connected in series, the equalization control device comprising:

The power interface is used for being connected with the energy storage converter;

a first serial interface for connecting with the plurality of battery packs in series;

The first equalization interfaces are used for being connected with one battery pack, and the first equalization interfaces are used for being respectively and correspondingly connected with the battery packs;

The first end of the change-over switch is connected with the power interface, the second end of the change-over switch is connected with the first serial interface, and the third end of the change-over switch is connected with the at least one first equalizing interface;

The control module is connected with the control end of the change-over switch and is used for acquiring parameters of the battery packs, determining whether the battery packs need to be balanced or not according to the parameters of the battery packs, controlling the first end of the change-over switch to be connected with the second end when the battery packs do not need to be balanced so as to control the first serial interface to be connected with the power interface, and sending charge and discharge parameters of the battery packs to the energy storage converter so as to enable the energy storage converter to charge and discharge the battery packs; when at least one battery pack needs to be balanced, a first end of the change-over switch is controlled to be connected with the third end, so that the first balancing interface correspondingly connected with the battery pack needing to be balanced is controlled to be connected with the power interface, and charge and discharge parameters of the battery pack needing to be balanced are sent to the energy storage converter, so that the energy storage converter charges and discharges the battery pack needing to be balanced.

2. The equalization control device of claim 1, wherein the equalization control device further comprises a plurality of equalization switches;

The first ends of the equalization switches are connected with the third ends of the change-over switches, and the second ends of the equalization switches are correspondingly connected with the first equalization interfaces respectively;

the control module is respectively connected with the control ends of the equalization switches, and is further used for controlling the first ends of the equalization switches correspondingly connected with the control module to be connected with the second ends of the equalization switches when at least one battery pack needs equalization.

3. The equalization control device of claim 1, wherein the equalization control device further comprises a first communication interface; the first communication interface is in communication connection with the plurality of battery packs, and is also connected with the control module; the first communication interface is used for receiving parameters sent by the plurality of battery packs and transmitting the parameters to the control module.

4. The equalization control device of claim 1, wherein the control module is further configured to send a connect command and a disconnect command to the energy storage converter; the communication instruction is used for enabling the energy storage converter to be communicated with the power interface, and the disconnection instruction is used for enabling the energy storage converter to be disconnected with the power interface.

5. The equalization control device of claim 4, wherein the equalization control device further comprises a second communication interface;

the second communication interface is used for being in communication connection with the energy storage converter;

The control module is further connected with the second communication interface, and is further used for sending a connection instruction, a disconnection instruction and charge and discharge parameters of the battery pack to the energy storage converter through the second communication interface.

6. The equalization control device of claim 1, wherein the equalization control device further comprises an operation panel;

The control module is further used for sending equalization prompt information through the operation panel to prompt a user that at least one battery pack in the energy storage system needs equalization, receiving equalization instructions input by the user through the operation panel, and controlling at least one corresponding first equalization interface to be connected with the power interface according to the equalization instructions.

7. The equalization control device of claim 1, wherein the battery pack includes a second serial interface and a second equalization interface, the second serial interface being connected in parallel with the second equalization interface, the second serial interface being for connection with the first serial interface or a second serial interface of another battery pack, the second equalization interface being for connection with the first equalization interface.

8. An equalization control system applied to an energy storage system, comprising an energy storage converter and an energy storage management unit, wherein the energy storage management unit comprises the equalization control device according to any one of claims 1-7.

9. The equalization control system of claim 8, wherein an operating voltage range of the energy storage converter covers a voltage range of one or more series-connected battery packs in the energy storage system and is capable of charging and discharging the one or more series-connected battery packs upon command.

10. An energy storage system comprising a plurality of battery packs in series and an equalization control system as claimed in claim 8 or 9.