WO2025119053A1 - 一种具有分断保护功能的电池包及储能系统 - Google Patents

一种具有分断保护功能的电池包及储能系统 Download PDF

Info

Publication number
WO2025119053A1
WO2025119053A1 PCT/CN2024/134887 CN2024134887W WO2025119053A1 WO 2025119053 A1 WO2025119053 A1 WO 2025119053A1 CN 2024134887 W CN2024134887 W CN 2024134887W WO 2025119053 A1 WO2025119053 A1 WO 2025119053A1
Authority
WO
WIPO (PCT)
Prior art keywords
current sensor
battery pack
controller
battery
energy storage
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/CN2024/134887
Other languages
English (en)
French (fr)
Inventor
余士江
朱军卫
李坪
叶万祥
曹震
周贺
付加光
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huawei Digital Power Technologies Co Ltd
Original Assignee
Huawei Digital Power Technologies Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huawei Digital Power Technologies Co Ltd filed Critical Huawei Digital Power Technologies Co Ltd
Publication of WO2025119053A1 publication Critical patent/WO2025119053A1/zh
Anticipated expiration legal-status Critical
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
    • H01M10/488—Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/502—Interconnectors for connecting terminals of adjacent batteries; Interconnectors for connecting cells outside a battery casing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
    • H01M2010/4271—Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing

Definitions

  • the present application relates to the field of energy technology, and in particular to a battery pack and energy storage system with a disconnection protection function.
  • battery energy storage systems are generally composed of multiple battery modules connected in series and then in parallel. Placing multiple battery modules together can easily lead to some safety hazards.
  • these defects may cause these battery cells to have abnormal conditions such as leakage failure during use, and these abnormal conditions will cause the battery cells to have short-circuit faults to the ground. Therefore, how to design a safe protection plan so that the fault will not spread even if the battery cell has a short-circuit fault to the ground is particularly critical.
  • the present application provides a battery pack and energy storage system with a disconnection protection function, which can quickly cut off the fault in the event of a battery pack failure (for example, a short circuit failure of the battery cell to the ground) to ensure the safe operation of the energy storage system.
  • a battery pack failure for example, a short circuit failure of the battery cell to the ground
  • an embodiment of the present application provides a battery pack, comprising a battery module, a disconnecting device, a first current sensor and a first controller, wherein the battery module comprises a plurality of single cells connected in series, the disconnecting device is connected in series with the battery module, a first end of the first current sensor is connected to a positive output end of the battery pack, a second end of the first current sensor is connected to a negative output end of the battery pack, the first current sensor is used to detect a current difference between a positive output end and a negative output end of the battery pack, and the first controller is used to control the disconnecting device to disconnect when the current difference detected by the first current sensor is greater than a first threshold value.
  • the first controller in the battery pack controls the disconnecting device in the battery pack to disconnect, thereby disconnecting the faulty circuit in the energy storage unit cluster, avoiding the fire hazard caused by voltage breakdown.
  • the embodiment of the present application does not limit the specific position of the disconnecting device in the battery pack, that is, the disconnecting device can be connected in series to the negative electrode of the battery module or the positive electrode of the battery module.
  • the first controller in one of the two battery packs with short-circuit faults to ground can trigger the protection mechanism to control the disconnecting device in the same battery pack to disconnect, thereby disconnecting the fault circuit in the energy storage unit cluster, avoiding the risk of fire caused by voltage breakdown.
  • the first controller and the first current sensor may be integrated on a circuit board.
  • the first current sensor may be an intelligent current sensor having a logic judgment function and a control function.
  • the first controller may be provided independently of the first current sensor.
  • the first controller may be a separate controller or may be integrated in other devices in the battery pack.
  • the first current sensor may adopt a residual current operated protective device (RCD).
  • RCD residual current operated protective device
  • the disconnecting device can be a switch, an exploding fuse, a contactor, a relay, a circuit breaker, an insulated gate bipolar transistor (IGBT), or a metal-oxide semiconductor field effect transistor (MOSFET).
  • IGBT insulated gate bipolar transistor
  • MOSFET metal-oxide semiconductor field effect transistor
  • the battery pack further includes a second current sensor and a second controller, wherein the second current sensor, the battery module and the disconnecting device are connected in series.
  • the second current sensor is used to detect the magnitude of the current passing through, and the second controller is used to control the disconnecting device to disconnect when the current detected by the second current sensor is greater than a second threshold value.
  • the first current sensor and the second current sensor are simultaneously arranged in the battery pack, and the short circuit fault of the battery cell to the ground is detected by two different detection methods, which can detect the fault more reliably and accurately, and perform disconnection protection in time to ensure the safe operation of the energy storage system.
  • the short circuit fault of multiple battery packs to the ground can still be detected by the other current sensor, which further improves the reliability of the system.
  • the second current sensor and the disconnecting device need to be connected in series on the same side of the battery module to achieve the detection and disconnection protection function of the short circuit fault of the battery cell to the ground.
  • the second current sensor and the disconnecting device can both be connected in series to the negative electrode of the battery module, and the second current sensor and the disconnecting device can also both be connected in series to the positive electrode of the battery module.
  • the second current sensor may be connected in series between the battery module and the disconnecting device, and the disconnecting device may also be connected in series between the battery module and the second current sensor.
  • the second controller and the second current sensor are integrated on a circuit board.
  • the second current sensor may be an intelligent current sensor having a logic judgment function and a control function.
  • the second controller may be provided independently of the second current sensor.
  • the second controller may be a separate controller or may be integrated in other devices in the battery pack.
  • the first controller and the second controller may be two independent controllers, for example, the first controller and the second controller may be integrated into different devices or circuit boards, respectively.
  • the first controller and the second controller may be integrated into a first current controller and a second current controller, respectively.
  • the first controller and the second controller may be the same controller, that is, the same controller performs the functions of the first controller and the second controller.
  • the functions of the first controller and the second controller may be performed by a BMS.
  • only one of the first current sensor and the second current sensor is in operation at the same time, so as to save electric energy while improving system reliability.
  • the first controller and the second controller are two independent controllers, it is also possible to control that only one of the first controller and the second controller is in operation at the same time, so as to save electric energy while improving system reliability.
  • a competition signal can be set to achieve that at the same time, only one of the first current sensor and the second current sensor is in operation.
  • the operation state of the second current sensor can be controlled according to the operation state of the first current sensor.
  • the second current sensor is controlled to stop operation, and when the first current sensor is in non-operational state, the second current sensor is controlled to operate.
  • the first current sensor has higher accuracy, faster response and better effect in detecting battery cell short-circuit faults than the second current sensor
  • setting the priority of the first current sensor higher than that of the second current sensor is beneficial to improving the detection effect of battery cell short-circuit faults.
  • the first controller is further used to control the second current sensor to not work when the first current sensor is in operation.
  • the first controller may send a first control signal to the second current sensor, the first control signal being used to indicate that the second current sensor is not working.
  • the operation switching between the first current sensor and the second current sensor can be controlled by the first controller.
  • the first controller is also used to send a second control signal to the second controller when the first current sensor is in an operating state, and the second control signal is used to indicate that the second current sensor is not working, and the second controller is used to control the second current sensor not to work according to the second control signal.
  • the second current sensor is powered by a battery module in the same battery pack.
  • the short-circuit fault detection and disconnection protection functions can be realized without an external power supply, which can ensure that the short-circuit fault of the battery cell to the ground can still be detected when the energy storage system is not connected to the AC grid or the AC grid connected to the energy storage system is out of power.
  • the second controller when the second controller is integrated into the second current sensor, the second controller can also be powered by the battery module in the same battery pack, that is, the same battery module is used to power the second current sensor and the second controller at the same time. In this way, it can be ensured that when the energy storage system is not connected to the AC power grid or the AC power grid connected to the energy storage system is out of power, the short circuit fault of the battery cell to the ground can still be detected and disconnection protection can be performed in time.
  • the first current sensor can be any one of a Hall sensor, a tunnel magnetoresistance sensor (Tunnel Magneto Resistance, TMR), an anisotropic magnetoresistance sensor (Anisotropic Magneto Resistive, AMR), and a giant magnetoresistance sensor (Giant Magneto Resistive, GMR).
  • TMR Tunnel Magneto Resistance
  • AMR anisotropic magnetoresistance sensor
  • GMR giant magnetoresistance sensor
  • the present application provides an energy storage system, which may include at least one energy storage unit cluster and a DC/AC converter, wherein the energy storage unit cluster includes at least two battery packs as described in any one of the first aspects, at least two battery packs are connected in series, and the energy storage unit cluster is connected to an AC power grid or a load via a DC/AC converter.
  • the energy storage unit cluster further includes an auxiliary source, and two ends of the auxiliary source are respectively connected to the positive output end and the negative output end of the energy storage unit cluster.
  • the first current sensor is powered by the auxiliary source.
  • the first controller when the first controller is integrated in the first current sensor, the first controller is powered by the auxiliary source.
  • the cluster-level auxiliary source When the energy storage system is connected to the AC grid and the AC grid is powered, the cluster-level auxiliary source is also powered.
  • the cluster-level auxiliary source is used to power the first current sensor and/or the first controller, thereby ensuring the normal operation of the first current sensor and/or the first controller.
  • Figure 1 is a schematic diagram of the structure of a battery cluster in an industrial and commercial scenario
  • FIG2 is a schematic diagram of the structure of a battery cluster in a power station scenario
  • FIG3 is a schematic diagram of the structure of an energy storage system provided in an embodiment of the present application.
  • FIG4 is a schematic diagram of the structure of another energy storage system provided in an embodiment of the present application.
  • FIG5 is a schematic diagram of the structure of another energy storage system provided in an embodiment of the present application.
  • FIG6 is a schematic diagram of the structure of another energy storage system provided in an embodiment of the present application.
  • FIG7 is a schematic diagram of the structure of an energy storage unit cluster provided in an embodiment of the present application.
  • FIG8 is a schematic diagram of a current loop of an energy storage system in normal operation provided by an embodiment of the present application.
  • FIG9 is a schematic diagram of a current loop in a case where two or more battery packs in an energy storage system provided by an embodiment of the present application have a short circuit to ground;
  • FIG10 is a schematic diagram of a current loop in another energy storage system provided by an embodiment of the present application when two or more battery packs have a short circuit to ground fault;
  • FIG11 is a schematic diagram of the structure of another energy storage unit cluster provided in an embodiment of the present application.
  • FIG12 is a schematic diagram of a current loop of another energy storage system provided in an embodiment of the present application under normal operating conditions
  • FIG13 is a schematic diagram of a current loop in another energy storage system provided by an embodiment of the present application when two or more battery packs have a short circuit to ground fault;
  • FIG14 is a schematic diagram of a current loop in another energy storage system provided in an embodiment of the present application when two or more battery packs have a short circuit to ground fault.
  • references to "one embodiment” or “some embodiments” etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application.
  • the phrases “in one embodiment”, “in some embodiments”, “in some other embodiments”, “in some other embodiments”, etc. that appear at different places in this specification do not necessarily refer to the same embodiment, but mean “one or more but not all embodiments", unless otherwise specifically emphasized in other ways.
  • the terms “including”, “comprising”, “having” and their variations all mean “including but not limited to”, unless otherwise specifically emphasized in other ways.
  • the terms “installed”, “connected”, “connected”, “fixed”, “connected”, “configured” and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, a detachable fixation, or an integral connection, etc.; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two devices or the interaction relationship between two devices, unless otherwise clearly defined.
  • the specific meanings of the above terms in this application can be understood according to specific circumstances.
  • battery energy storage systems are generally composed of multiple battery modules connected in series and then in parallel. Placing multiple battery modules together can easily lead to some safety hazards.
  • these defects may cause these battery cells to have abnormal conditions such as leakage failure during use, and these abnormal conditions will cause the battery cells to have short-circuit faults to the ground. Therefore, how to design a safe protection plan so that the fault will not spread even if the battery cell has a short-circuit fault to the ground is particularly critical.
  • the prior art adopts a variety of methods to ensure the safe operation of the energy storage system.
  • a common fuse is usually configured in the battery pack, and a cluster-level high-voltage common fuse is configured in the cluster control box.
  • the common fuse in the battery pack and the high-voltage common fuse in the cluster control box will blow when the current passing through is greater than a threshold, thereby disconnecting and protecting against differential mode faults caused by failure of components such as power converters.
  • the cluster control box is also equipped with a cluster-level insulation impedance detection function and a cluster-level switch.
  • the insulation impedance detection circuit can identify the insulation impedance abnormality before the system is powered on, and control the cluster-level switch to disconnect for disconnection protection.
  • the insulation impedance detection circuit cannot identify the abnormality, so it cannot play an effective protective role during the power-on operation of the system.
  • FIG. 1 is a schematic diagram of the structure of a battery cluster in an industrial and commercial scenario. See Figure 1.
  • the AC side of the power converter is grounded. Therefore, when a single-point insulation failure to the ground occurs in the battery pack (that is, a short circuit fault occurs to the ground in a single battery pack), the cluster-level RCD can detect the fault current and trigger the cluster-level switch for disconnection protection.
  • the cluster-level switch can detect the fault current and trigger the cluster-level switch for disconnection protection.
  • the voltage breakdown between the two battery packs with a short circuit fault to the ground in the battery cluster may still cause a fire risk.
  • FIG 2 is a schematic diagram of the structure of a battery cluster in a power station scenario. See Figure 2.
  • the AC side of the power converter is not grounded. Therefore, regardless of whether a single-point short-circuit fault or a multi-point short-circuit fault occurs in a battery pack (i.e., a short-circuit fault occurs in the cells of multiple battery packs), the cluster-level RCD cannot detect the fault current and cannot trigger the cluster-level switch for disconnection protection.
  • the cluster-level RCD cannot detect a short-circuit fault in the cells of the PACK and cannot trigger disconnection protection.
  • the present application provides a battery pack and energy storage system that can quickly cut off the fault and ensure the safe operation of the energy storage system when a short circuit to ground occurs in the battery cells of two or more battery packs in a battery cluster.
  • FIGs 3 to 6 are schematic diagrams of the structures of four energy storage systems provided by the embodiment of the present application.
  • the energy storage system provided by the embodiment of the present application includes one or more energy storage unit clusters (two energy storage unit clusters are shown in the figure, battery cluster 1 and battery cluster 2), and an energy storage unit cluster may include at least two battery packs (each battery cluster in the figure includes N battery packs), and each battery pack is connected in series.
  • an energy storage unit cluster can be composed of at least two battery packs connected in series.
  • the internal structure of the battery pack will be described in detail below.
  • the energy storage system provided in the embodiment of the present application involves a multi-layer structure
  • the first layer is called an energy storage system or a battery energy storage system
  • the second layer is called an energy storage unit cluster or a battery cluster
  • the third layer is called a battery pack or PACK
  • the fourth layer is called a battery module.
  • the different names of the same layer structure mentioned above have the same meaning in the embodiment of the present application, and are all used to refer to this specific layer structure, and the embodiment of the present application does not distinguish them.
  • the battery module can be composed of multiple battery cells connected in series
  • the battery pack can include a battery module, a battery management unit (battery management unit, BMU) and an optimizer
  • the battery cluster can include multiple battery packs connected in series
  • the energy storage system can include multiple battery clusters connected in parallel.
  • one or more energy storage unit clusters can be illustrated by taking battery clusters 1 to 2 as examples, wherein battery cluster 1 can be composed of PACK11 to PACK1n connected in series, and battery cluster 2 can be composed of PACK21 to PACK2n connected in series, and n is an integer.
  • each battery cluster in the energy storage system can be coupled to the DC bus through a direct current (DC)/direct current converter (DC/DC converter), and one battery cluster is coupled to the DC bus through a DC/DC converter.
  • DC direct current
  • DC/DC converter direct current converter
  • battery cluster 1 can be coupled to the DC bus through converter DC/DC1
  • battery cluster 2 can be coupled to the DC bus through converter DC/DC2.
  • Each battery cluster is coupled to the DC bus through a DC/DC converter to achieve simple parallel expansion of multiple battery clusters, which can increase the energy storage capacity of the energy storage system.
  • the DC/DC converter can also achieve flexible control of the energy of a single battery cluster and rapid switching of a single battery cluster under abnormal conditions, which has strong applicability. After multiple battery clusters are connected in parallel, they can share a DC/AC inverter (DC/AC converter) to convert DC power into AC power and exchange energy with the AC power grid.
  • DC/AC inverter DC/AC inverter
  • the DC/DC converter can be a bidirectional DC/DC converter, and the circuit topology of the bidirectional DC/DC converter can be an isolated circuit topology or a non-isolated circuit topology.
  • the boost ratio of the bidirectional DC/DC converter is determined by the voltage of the DC bus and the port voltage of the battery cluster. Taking battery cluster 1 as an example, since the port voltage of the battery changes with the energy storage capacity of the battery, the port voltage of battery cluster 1 changes with the number of battery packs connected in series in battery cluster 1. When the number of battery packs connected in series in battery cluster 1 changes greatly, the port voltage of battery cluster 1 will also change greatly.
  • the port voltage of the battery pack is 50V
  • the port voltage of battery cluster 1 is 100V
  • the port voltage of battery cluster 1 is 1500V, that is, the upper limit voltage of the low-voltage system, so the port voltage of battery cluster 1 can be a wide range of output voltages, such as 100V to 1500V.
  • the converter DC/DC1 can usually be implemented using a non-isolated circuit topology and can be designed as a converter with a wide range of input/output capabilities, so that it can flexibly adapt to different input/output voltages.
  • the circuit topology of the bidirectional DC/DC converter (including converters DC/DC1 and DC/DC2, etc.) can be selected from a boost circuit, a flying capacitor boost circuit, a flying capacitor multilevel circuit, a positive and negative symmetrical three-level boost circuit, a four-switch buck-boost circuit, etc., which can be determined according to the actual application scenario requirements.
  • the boost ratio of the converter DC/DC1 can be determined by the voltage of the DC bus and the port voltage of the battery cluster 1, which can be determined according to the actual application scenario.
  • a centralized monitoring system (battery control unit, BCU) can be added for each battery cluster, wherein one battery cluster corresponds to one centralized monitoring system BCU.
  • battery cluster 1 can correspond to the centralized monitoring system BCU1 in converter DC/DC1
  • battery cluster 2 can correspond to the centralized monitoring system BCU2 in converter DC/DC2.
  • the centralized monitoring system of each battery cluster can be connected to each battery pack in the battery cluster through a control bus, and the centralized monitoring system can interact with each battery pack in the battery cluster in real time, so as to achieve real-time and unified monitoring of the battery packs in each battery cluster, thereby achieving flexible control of the energy storage system, and having strong applicability.
  • the centralized monitoring system BCU when the centralized monitoring system BCU is an independently placed circuit module, the centralized monitoring system corresponding to a single battery cluster interacts with the controller in the DC/DC converter, and the centralized monitoring system connects each battery pack in the battery cluster through a control bus.
  • the information interaction mode between the centralized monitoring system BCU and the battery pack can also be wireless communication, DC power carrier communication, etc., which can be determined according to the actual application scenario, with flexible operation and high applicability.
  • the centralized monitoring system BCU of a single battery cluster when the centralized monitoring system BCU of a single battery cluster is integrated as a separate circuit board or circuit module in the DC/DC converter to which the battery cluster is connected, the system structure of the energy storage system can be simplified.
  • integrating the centralized monitoring system of a single battery cluster into the DC/DC converter is beneficial to the connection of the control bus.
  • a BMU in order to realize the state monitoring and control of the battery pack, a BMU may be added to the battery pack of each battery cluster, and the BMU may include a module battery management system (mBMS) and corresponding sampling control modules, communication modules, power supply modules, switch bridge arm drive control circuits, etc., for realizing the state detection and control of each energy storage element group (i.e., each battery pack) in the battery pack.
  • the centralized monitoring system BCU of the battery cluster is connected in communication with the battery management unit BMS in the battery pack to jointly realize the state detection and control of the battery pack.
  • a DC/AC converter may be configured separately for each battery cluster, that is, multiple battery clusters do not share a DC/AC converter, and the battery clusters directly output the converted AC power to the AC grid.
  • battery cluster 1 may be coupled to the AC grid through converter DC/DC1 and converter DC/AC1
  • battery cluster 2 may be coupled to the AC grid through converter DC/DC2 and converter DC/AC2.
  • Each battery cluster is coupled to the AC grid through a DC/DC converter and a DC/AC converter to achieve a simple parallel expansion of multiple battery clusters, which can increase the energy storage capacity of the energy storage system and exchange energy with the AC grid.
  • each battery cluster may also be configured with a cluster control box for unified control of a single battery cluster.
  • Cluster-level fuses, cluster-level insulation impedance detection, cluster-level switches and other devices may be provided in the cluster control box to achieve cluster-level management and protection of the battery.
  • battery cluster 1 may be coupled to the DC bus via cluster control box 1
  • battery cluster 2 may be coupled to the DC bus via cluster control box 2.
  • Each battery cluster may be coupled to the DC bus via a cluster control box to achieve simple parallel expansion of multiple battery clusters, thereby increasing the energy storage capacity of the energy storage system.
  • a common DC/AC converter may be used to convert DC power into AC power, and exchange energy with the AC power grid.
  • each battery cluster can be individually configured with a DC/AC converter on the basis of configuring a cluster control box for each battery cluster, that is, multiple battery clusters do not share a DC/AC converter, and the battery cluster directly outputs the converted AC power to the AC power grid.
  • the electric energy output by battery cluster 1 after passing through cluster control box 1 can be coupled to the AC power grid through converter DC/AC1
  • the electric energy output by battery cluster 2 after passing through cluster control box 2 can be coupled to the AC power grid through converter DC/AC2.
  • Each battery cluster is coupled to the AC power grid through a DC/AC converter to achieve a simple parallel expansion of multiple battery clusters, which can increase the energy storage capacity of the energy storage system and exchange energy with the AC power grid.
  • FIG. 7 is a schematic diagram of the structure of an energy storage unit cluster provided in the embodiment of the present application, and the energy storage unit cluster includes multiple battery packs connected in series and a cluster control box.
  • each battery pack in the embodiment of the present application includes a battery module, a disconnecting device (a switch is taken as an example in Figure 7), a first current sensor (RCD is taken as an example in Figure 7) and a first controller (not shown in Figure 7).
  • the energy storage unit cluster shown in Figure 7 includes PACK1...PACKn-1, PACKn, wherein PACK1 includes battery module 1, disconnecting device 1 and RCD1, and PACKn includes battery module n, disconnecting device n and RCDn.
  • the battery module includes a plurality of single cells, which are connected in series to expand the capacity of the battery pack. It should be understood that the number of single cells in the battery module can be flexibly set according to actual needs.
  • the disconnecting device is connected in series with the battery module.
  • the disconnecting device is connected in series with the negative electrode of the battery module. It should be understood that the disconnecting device can also be connected in series with the positive electrode of the battery module.
  • the embodiment of the present application does not limit the relative position of the disconnecting device and the battery module.
  • the disconnecting device in the embodiment of the present application is a controllable disconnecting device, that is, the disconnecting device is disconnected under the control of a control signal, thereby disconnecting the current path in the battery pack.
  • the disconnecting device can be a switch, an explosive fuse, a contactor, a relay, a circuit breaker, an insulated gate bipolar transistor (IGBT), or a metal-oxide semiconductor field effect transistor (MOSFET).
  • the switch can be disconnected under the control of a control signal, thereby disconnecting the current path in the battery pack.
  • the disconnecting device adopts an explosive fuse the explosive fuse can be disconnected under the control of a control signal, thereby disconnecting the current path in the battery pack.
  • any device that can be disconnected according to a control signal can be used as a controllable disconnecting device in the embodiments of the present application, and the controllable disconnecting device can be flexibly selected according to actual needs.
  • the first end of the first current sensor is connected to the positive output end of the battery pack, and the second end of the first current sensor is connected to the negative output end of the battery pack, so as to detect the current difference between the positive output end and the negative output end of the battery pack.
  • the first current sensor can be a device for detecting the current difference, and in another possible implementation, the first current sensor can also be a circuit for detecting the current difference.
  • the first current sensor can be a residual current operated protective device (RCD). It should be understood that any sensor that can be connected to the two ends of the battery pack and obtain the current difference between the two ends can be used as the first current sensor in the embodiment of the present application, and the first current sensor can be flexibly selected according to actual needs.
  • the first controller is used to control the above-mentioned disconnecting device to disconnect when the current difference between the positive output terminal and the negative output terminal of the battery pack is greater than a first threshold value, that is, the first controller always controls the above-mentioned disconnecting device to disconnect when the current difference detected by the first current sensor is greater than the first threshold value.
  • the first controller and the first current sensor may be integrated on a circuit board.
  • the first current sensor may be an intelligent current sensor with logic judgment function and control function.
  • the first controller may be set independently of the first current sensor.
  • the first controller may be a separate controller or may be integrated in other devices in the battery pack.
  • the first controller may also be a BMS in the battery pack.
  • the energy storage unit cluster provided in the embodiment of the present application may not be provided with a cluster control box.
  • a cluster control box may also be provided on the energy storage unit side provided in the embodiment of the present application, and a cluster-level fuse, or a cluster-level switch, or a cluster-level insulation impedance detection circuit may be provided in the cluster control box.
  • an RCD may be provided in the cluster control box to detect the current difference between the positive output terminal and the negative output terminal of the battery cluster, further improving the safety of the energy storage system. Based on cost considerations, after the first current sensor is provided in the battery pack, the RCD may no longer be provided in the cluster control box.
  • FIG8 is a schematic diagram of the current loop of the energy storage system shown in FIG7 under normal operation.
  • the currents at both ends of a battery pack in the energy storage unit cluster should be roughly equal, that is, when the energy storage system is operating normally, there is no current difference at both ends of the battery pack, or only a small current difference. Therefore, by reasonably setting the first threshold, when the energy storage system is operating normally, the current difference detected by the first current sensor will not be greater than the first threshold, and the disconnecting device is in a closed state.
  • FIG9 is a schematic diagram of the current loop in the case where two or more battery packs in the energy storage system shown in FIG7 have a short circuit to ground fault.
  • the battery cells in battery pack 1 and battery pack n-1 both have a short circuit to ground fault.
  • the voltage of multiple battery cells connected in series is very large, it is very easy to cause a fire hazard due to voltage breakdown.
  • the disconnecting device in the same battery pack is controlled to disconnect, so as to disconnect the fault circuit in the energy storage unit cluster.
  • the disconnecting device is connected in series to the negative electrode of the battery module.
  • FIG10 is a schematic diagram of a current loop in another energy storage system provided by an embodiment of the present application when two or more battery packs have a short circuit to ground fault.
  • the difference between FIG10 and FIG9 is that the disconnecting device in FIG9 is connected in series to the negative electrode of the battery module, while the disconnecting device in FIG10 is connected in series to the positive electrode of the battery module.
  • the disconnecting device in FIG9 is connected in series to the negative electrode of the battery module, while the disconnecting device in FIG10 is connected in series to the positive electrode of the battery module.
  • FIG10 when a short circuit to ground fault occurs in the battery cells in PACK1 and PACKn-1, there is a current difference between the positive output terminal and the negative output terminal of PACK n-1, and the current difference detected by the first current sensor in PACK n-1 is greater than the first threshold, thereby triggering the first controller in PACK n-1 to control the disconnecting device n-1 to disconnect.
  • the disconnecting device n-1 can disconnect the fault circuit in FIG10 to avoid the risk of fire caused by voltage breakdown. It can be seen that whether the disconnecting device is connected in series to the positive electrode of the battery module or the disconnecting device is connected in series to the negative electrode of the battery module, it can play a role in disconnection protection, and the embodiment of the present application does not limit this.
  • FIG11 is a schematic diagram of the structure of another energy storage unit cluster provided in an embodiment of the present application.
  • the battery pack provided in an embodiment of the present application further includes a second current sensor (TMR is used as an example in FIG11 ) and a second controller (not shown in FIG11 ), and the disconnecting device in FIG11 is used as an example of an explosive fuse.
  • TMR is used as an example in FIG11
  • the disconnecting device in FIG11 is used as an example of an explosive fuse.
  • the energy storage unit cluster shown in FIG11 includes PACK1...PACKn-1, PACKn, wherein PACK1 includes a battery module 1, a disconnecting device 1, TMR1 and RCD1, and PACKn includes a battery module n, a disconnecting device n, TMRn and RCDn.
  • the second current sensor is connected in series with the battery module and the disconnecting device in the battery pack.
  • the second current sensor is connected in series between the negative electrode of the battery module and the disconnecting device. It should be understood that the second current sensor can also be connected in series with the positive electrode of the battery module.
  • the second current sensor is used to detect the magnitude of the current passing through the series circuit.
  • the second current sensor can be a device for detecting current, and in another possible implementation, the second current sensor can also be a circuit for detecting current.
  • the first current sensor can be any one of a Hall sensor, a tunnel magnetoresistance sensor (Tunnel Magneto Resistance, TMR), an anisotropic magnetoresistance sensor (Anisotropic Magneto Resistive, AMR), and a giant magnetoresistance sensor (Giant Magneto Resistive, GMR).
  • TMR Tunnel Magneto Resistance
  • AMR anisotropic magnetoresistance sensor
  • GMR giant magnetoresistance sensor
  • the second current sensor and the disconnecting device need to be connected in series on the same side of the battery module in order to realize the detection and disconnection protection function of the short circuit fault of the battery cell to the ground.
  • the second current sensor and the disconnecting device can both be connected in series to the negative pole of the battery module, and the second current sensor and the disconnecting device can also be connected in series to the positive pole of the battery module.
  • the embodiment of the present application does not limit the relative position relationship between the second current sensor and the disconnecting device.
  • one end of the TMR is connected to the positive output end of the battery module, the other end of the TMR is connected to one end of the disconnecting device, and the other end of the disconnecting device is connected to the positive output end of the battery pack.
  • one end of the disconnecting device is connected to the positive output end of the battery module, the other end of the disconnecting device is connected to one end of the TMR, and the other end of the TMR is connected to the positive output end of the battery pack.
  • one end of the TMR is connected to the negative output end of the battery module, the other end of the TMR is connected to one end of the disconnecting device, and the other end of the disconnecting device is connected to the negative output end of the battery pack.
  • one end of the disconnecting device is connected to the negative output end of the battery module, the other end of the disconnecting device is connected to one end of the TMR, and the other end of the TMR is connected to the negative output end of the battery pack.
  • the second controller is used to control the disconnecting device in the battery pack to disconnect when the current detected by the second current sensor is greater than the second threshold value.
  • the second controller and the second current sensor are integrated on a circuit board.
  • the second current sensor can be an intelligent current sensor with logic judgment function and control function.
  • the second controller can be set independently of the second current sensor.
  • the second controller can be a separate controller or integrated in other devices in the battery pack.
  • the second controller can also be a BMS in the battery pack.
  • the first controller and the second controller may be two independent controllers, for example, the first controller and the second controller may be integrated in different devices or circuit boards, respectively.
  • the first controller and the second controller may be integrated in a first current controller and a second current controller, respectively.
  • the first controller and the second controller may be the same controller, that is, the same controller performs the functions of the first controller and the second controller.
  • the functions of the first controller and the second controller may be performed by a BMS.
  • FIG12 is a schematic diagram of the current loop of the energy storage system shown in FIG11 under normal operation.
  • the current value in the current loop within the energy storage unit cluster is relatively stable, and usually only has slight fluctuations. Therefore, by reasonably setting the second threshold, when the energy storage system is operating normally, the current detected by the second current sensor will not be greater than the second threshold, and the disconnecting device is in a closed state.
  • FIG13 is a schematic diagram of the current loop in the case of a short circuit to ground failure of two or more battery packs in the energy storage system shown in FIG11. As shown in FIG13, the cells in battery pack 1 and battery pack n-1 both have a short circuit to ground failure.
  • the disconnecting device in the same battery pack is controlled to be disconnected.
  • the disconnecting device 1 can disconnect the fault circuit in FIG13 , thereby avoiding the risk of fire caused by voltage breakdown.
  • FIG14 is a schematic diagram of a current loop in the case of a short circuit to ground fault in two or more battery packs in the energy storage system shown in FIG11.
  • the difference between FIG14 and FIG13 is that the second current sensor and the disconnecting device in FIG13 are connected in series to the negative electrode of the battery module, while the second current sensor and the disconnecting device in FIG14 are connected in series to the positive electrode of the battery module.
  • the second current sensor and the disconnecting device are connected in series to the positive electrode of the battery module, when the battery cells in PACK1 and PACKn-1- have a short circuit to ground fault, the current detected by the second current sensor in PACKn-1 is greater than the second threshold value, thereby triggering the second controller in PACKn-1 to control the disconnecting device n-1 to disconnect.
  • the disconnecting device n-1 can disconnect the fault loop in FIG14, thereby avoiding the risk of fire caused by voltage breakdown.
  • the disconnecting protection function can be achieved, and the embodiment of the present application is not limited to this.
  • the second current sensor can exist independently of the first current sensor, that is, a second current sensor and a disconnecting device are provided in the battery pack, and the second current sensor is used to detect a short circuit fault of the battery cell to ground, and the disconnecting device is controlled to disconnect, so as to achieve the effect of disconnection protection under fault conditions.
  • a second current sensor and a disconnecting device are provided in the battery pack, and the second current sensor is used to detect a short circuit fault of the battery cell to ground, and the disconnecting device is controlled to disconnect, so as to achieve the effect of disconnection protection under fault conditions.
  • only one set of fault detection and disconnection protection logic is provided in the battery pack.
  • a first current sensor and a second current sensor may be simultaneously provided in the battery pack, and two different control logics may be used to detect the short-circuit fault of the battery cell to the ground, so that the fault can be detected more reliably and accurately, and disconnection protection can be performed in time to ensure the safe operation of the energy storage system.
  • another set of control logic can still be used to detect the short-circuit fault of multiple battery packs to the ground, further improving the reliability of the system.
  • the first current sensor and the second current sensor it is also possible to control only one of the first current sensor and the second current sensor to be in the operating state at the same time, so as to save electric energy under the premise of improving system reliability.
  • the first controller and the second controller are two independent controllers, it is also possible to control only one of the first controller and the second controller to be in the operating state at the same time, so as to save electric energy under the premise of improving system reliability.
  • the operating state refers to the current sensor or controller being powered on and working normally to realize the detection or control function
  • the non-operating state corresponds to the operating state. In the non-operating state, the current sensor or controller does not work and does not consume power.
  • the above functions can be achieved by setting a competition signal.
  • the operating state of the second current sensor is controlled according to the operating state of the first current sensor. Specifically, when the first current sensor is in an operating state, the second current sensor is controlled to stop operating, and when the first current sensor is in a non-operating state, the second current sensor is controlled to operate. Because under normal circumstances, the first current sensor has higher accuracy, faster response, and better effect in detecting a short circuit fault of a battery cell to the ground than the second current sensor, therefore, setting the priority of the first current sensor higher than that of the second current sensor is beneficial to improving the detection effect of a short circuit fault of a battery cell to the ground.
  • the first controller when the functions of the first controller and the second controller are implemented by a centralized controller (such as a BMS) (here the centralized controller is referred to as the first controller), the first controller is also used to send a first control signal to the second current sensor when the first current sensor is in operation, and the first control signal is used to indicate that the second current sensor is not working.
  • the second current sensor is in operation and detects the current passing through in real time.
  • the first current sensor starts to work (for example, the condition for the first current sensor to start working may be that the first current sensor is powered on), and when the first controller detects that the first current sensor starts to work, it sends a first control signal to the second sensor, and the second sensor stops working after receiving the first control signal (the second sensor switches to a non-operating state).
  • the first controller continuously sends the first control signal to the second current sensor, or the first controller sends the first control signal to the second current sensor at a preset time interval.
  • the first controller stops sending the first control signal it means that the first current sensor stops working (is no longer in operation). At this time, the second sensor does not receive the first control signal and starts working again.
  • the first controller stops sending the first control signal after sending the first control signal until it detects that the first current sensor stops working, and then sends a third control signal to the second current sensor, the third control signal being used to instruct the second current sensor to operate.
  • the second current sensor resumes working after receiving the third control signal.
  • the operation switching between the first current sensor and the second current sensor can be controlled by the first controller.
  • the first controller is also used to send a second control signal to the second controller when the first current sensor is in operation, and the second control signal is used to indicate that the second current sensor is not working.
  • the second current sensor is in operation and detects the current passing through in real time. At the first moment, the first current sensor starts to work (for example, the condition for the first current sensor to start working may be that the first current sensor is powered on).
  • the first controller When the first controller detects that the first current sensor starts to work, it sends a first control signal to the second controller. After receiving the first control signal, the second controller controls the second current sensor to stop working.
  • the first controller when the first current sensor is in operation, the first controller continuously sends the first control signal to the second controller, or the first controller sends the first control signal to the second controller at a preset time interval.
  • the first controller stops sending the first control signal it means that the first current sensor stops working (is no longer in operation). At this time, the second controller cannot receive the first control signal, and the second controller controls the second current sensor to restart working.
  • the first controller stops sending the first control signal after sending the first control signal, until it detects that the first current sensor stops working, and then sends a third control signal to the second controller, and the third control signal is used to indicate that the second current sensor is running.
  • the second controller controls the second current sensor to restart working after receiving the third control signal.
  • the operation switching between the first current sensor and the second current sensor can also be controlled by the second controller.
  • the second controller is also used to control the second current sensor not to work when the first current sensor is in operation. At this time, the second controller detects the working state of the first current sensor in real time, and controls the working state of the second current sensor according to the working state of the first current sensor.
  • the first current sensor and the second current sensor can also be controlled to work under different circumstances to realize the detection of battery cell faults at all times. Specifically, when the AC power grid connected to the energy storage system is powered, the first current sensor can be used to detect the battery cell short-circuit fault to the ground, and when the AC power grid connected to the energy storage system is out of power, or the energy storage system is not connected to the AC power grid, the second current sensor can be used to detect the battery cell short-circuit fault to the ground. In this way, whether the energy storage system is powered on and running, or when the energy storage system is not powered on during transportation, storage, etc., the battery cell short-circuit fault detection and disconnection protection can be realized.
  • the first current sensor can be powered by a cluster-level auxiliary source, and then detect the short-circuit fault of the battery cell to ground when the cluster-level auxiliary source is powered, and control the disconnecting device to perform disconnection protection.
  • the cluster-level auxiliary source can be arranged in a cluster control box, the first end of the cluster-level auxiliary source is connected to the positive output end of the energy storage unit cluster, and the second end of the cluster-level auxiliary source is connected to the negative output end of the energy storage unit cluster.
  • the cluster-level auxiliary source can be powered by a DC bus, or the cluster-level auxiliary source can also be powered directly by an AC power grid.
  • the first controller When the first controller is integrated in the first current sensor, the first controller may also be powered by the cluster-level auxiliary source. When the first controller is integrated in other devices, or when the first controller is an independent controller, the first controller may also be powered by the cluster-level auxiliary source.
  • the cluster-level auxiliary source When the energy storage system is connected to the AC grid and the AC grid is powered, the cluster-level auxiliary source is also powered.
  • the cluster-level auxiliary source is used to power the first current sensor and/or the first controller, thereby ensuring the normal operation of the first current sensor and/or the first controller.
  • the battery cell short-circuit fault can still be detected, the above-mentioned second current sensor can be powered by the battery module in the same battery pack, thereby realizing the short-circuit fault detection and disconnection protection function without the need for an external power supply.
  • the second controller When the second controller is integrated in the second current sensor, the second controller can also be powered by the battery module in the same battery pack, that is, the same battery module is used to power the second current sensor and the second controller at the same time. In this way, it can be ensured that when the energy storage system is not connected to the AC power grid or the AC power grid connected to the energy storage system is out of power, the short circuit fault of the battery cell to the ground can still be detected and disconnected for protection in time.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)

Abstract

本申请提供了一种具有分断保护功能的电池包及储能系统，该电池包中包括由多个单体电芯组成的电池模组，与电池模组串联连接的分断器件，电流传感器和控制器，电流传感器的第一端连接电池包的正输出端，电流传感器的第二端连接电池包的负输出端，以用于检测电池包的正输出端和负输出端之间的电流差，控制器用于在电流传感器检测到的电流差大于第一阈值的情况下控制分断器件断开，以在电池包中的电芯发生对地短路故障的情况下快速切断故障，确保整个储能系统安全运行。

Description

一种具有分断保护功能的电池包及储能系统
本申请要求于2023年12月8日提交中国国家知识产权局、申请号为202311691834.7、发明名称为“一种具有分断保护功能的电池包及储能系统”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及能源技术领域，尤其涉及一种具有分断保护功能的电池包及储能系统。
背景技术
目前，随着新能源占比逐步提升，为解决大规模光伏和风力发电等发电间歇不稳定问题，电池储能系统的配置日益重要，且储能系统的配置占比也日益提升。受限于电芯及电池模组加工颗粒度的大小限制，电池储能系统一般由多个电池模组串联后再并联组成，多个电池模组放置在一起容易导致一些安全隐患。并且，由于电芯来料、加工制程等过程中会不可避免的造成某些电芯存在一定的缺陷，这些缺陷可能会导致这些电芯在使用过程中发生例如漏液失效等异常情况，这些异常情况会导致电芯发生对地短路故障。因此，如何设计安全的保护方案，做到即使电芯发生对地短路故障等情况时，故障仍不会扩散尤为关键。
发明内容
针对上述问题，本申请提供了一种具有分断保护功能的电池包及储能系统，在电池包发生故障(例如，电芯对地短路故障)的情况下，能够快速切断故障，确保储能系统的安全运行。
第一方面，本申请实施例提供一种电池包，该电池包包括电池模组，分断器件，第一电流传感器和第一控制器，其中，电池模组包括多个串联连接的单体电芯，分断器件与电池模组串联连接，第一电流传感器的第一端连接电池包的正输出端，第一电流传感器的第二端连接电池包的负输出端，第一电流传感器用于检测电池包的正输出端和负输出端之间的电流差，第一控制器用于在第一电流传感器检测到的电流差大于第一阈值的情况下控制分断器件断开。
当同一个电池簇内的两个电池包发生对地短路故障时，相当于多个电芯在没有负载的情况下串联在一起，由于多个电芯串联的电压很大，极易由于电压击穿导致起火危险。此时，由于储能单元簇内存在两个电流回路，导致发生对地短路故障的两个电池包的两端的电流大小不相同，即，发生对地短路故障的两个电池包的两端均存在电流差。此时，当发生故障的电池包内的第一电流传感器检测到的电流差大于第一阈值时，该电池包内的第一控制器控制该电池包内的分断器件断开，进而断开储能单元簇内的故障回路，避免了由于电压击穿导致的起火危险。
应当理解，本申请实施例对分断器件在电池包中的具体位置不作限定，也即，分断器件既可以串联在电池模组的负极，也可以串联在电池模组的正极。在两种情况下，两个发生对地短路故障的电池包中都有一个电池包中的第一控制器能够触发保护机制，控制同一个电池包中的分断器件断开，进而断开储能单元簇内的故障回路，避免了由于电压击穿导致的起火危险。
可选的，第一控制器和第一电流传感器可以集成在一块电路板上，换言之，第一电流传感器可以是一个具有逻辑判断功能和控制功能的智能电流传感器。
可选的，第一控制器可以独立于第一电流传感器设置，第一控制器可以是单独的控制器，也可以集成在在电池包中的其他器件中。
可选的，第一电流传感器可以采用剩余电流动作保护器(residual current operated protective device，RCD)。
可选的，分断器件可以采用开关、爆炸熔丝、接触器、继电器、断路器、绝缘栅双极型晶体管(Insulated Gate Bipolar Transistor,IGBT)、或者金属-氧化物半导体场效应晶体管(Metal Oxide Semiconductor Field Effect Transistor,MOSFET)。
可选的，上述电池包中还包括第二电流传感器和第二控制器，其中，第二电流传感器和上述电池模组和上述分断器件串联连接。第二电流传感器用于检测通过的电流大小，第二控制器用于在第二电流传感器检测到的电流大于第二阈值的情况下控制上述分断器件断开。
当同一个电池簇内的两个电池包发生对地短路故障时，相当于多个电芯在没有负载的情况下串联在一起，由于多个电芯串联的电压很大，极易由于电压击穿导致起火危险。此时，电流回路中的电流会激增，也就是说，相比于电池包正常工作时的电流回路而言，电池包故障时的故障电流回路中的电流会激增，也即，第二电流传感器中流经的电流会激增。当电池包内的第二电流传感器检测到的电流大小超过第二阈值时，控制同一个电池包内的分断器件断开，可以断开故障回路，进而避免由于电压击穿导致的起火风险。
在电池包中同时设置第一电流传感器和第二电流传感器，通过两套不同的检测方法检测电芯对地短路故障，能够更加可靠准确的检测到故障，及时进行分断保护，保障储能系统的安全运行。除此之外，当第一电流传感器或者第二电流传感器中的一个发生故障时，仍然可以通过另一个电流传感器检测多个电池包对地短路的故障，进一步提高了系统的可靠性。
应当了解，第二电流传感器和分断器件需要串联在电池模组的同一侧，才能够实现对电芯对地短路故障的检测和分断保护功能。可选的，第二电流传感器和分断器件可以均串联在电池模组的负极，第二电流传感器和分断器件也可以均串联在电池模组的正极。
可选的，第二电流传感器可以串联在电池模组和分断器件之间，分断器件也可以串联在电池模组和第二电流传感器之间。
可选的，第二控制器与第二电流传感器集成在一块电路板上，换言之，第二电流传感器可以是一个具有逻辑判断功能和控制功能的智能电流传感器。
可选的，第二控制器可以独立于第二电流传感器设置，第二控制器可以是单独的控制器，也可以集成在在电池包中的其他器件中。
可选的，第一控制器和第二控制器可以是两个独立的控制器，例如，第一控制器和第二控制器可以分别集成在不同的器件或者电路板中。例如，第一控制器和第二控制器可以分别集成在第一电流控制器和第二电流控制器中。
可选的，第一控制器和第二控制器可以是同一个控制器，即，用同一个控制器执行第一控制器和第二控制器的功能。例如，可以由BMS执行第一控制器和第二控制器的功能。
可选的，第一电流传感器和第二电流传感器在同一时刻只有一个处于运行状态，以在提高系统可靠性的前提下节约电能。
可选的，当第一控制器和第二控制器为两个独立的控制器的情况下，也可以控制同一时刻下，第一控制器和第二控制器中只有一个处于运行状态，以在提高系统可靠性的前提下节约电能。
可选的，可以通过设置一个竞争信号来实现在同一时刻，第一电流传感器和第二电流传感器只有一个处于运行状态。具体的，可以根据第一电流传感器的运行状态控制第二电流传感器的运行状态。当第一电流传感器处于运行状态时，控制第二电流传感器停止运行，当第一电流传感器处于非运行状态时，控制第二电流传感器运行。
由于通常情况下，第一电流传感器的相比于第二电流传感器而言，检测电芯对地短路故障的精度更高，响应更快，效果更好，因此，设置第一电流传感器的优先级高于第二电流传感器的优先级，有利于提高电芯对地短路故障得检测效果。
可选的，当第一控制器的功能和第二控制器的功能由一个集中控制器(例如BMS)实现的情况下(这里称该集中控制器为第一控制器)，第一控制器还用于，在第一电流传感器处于运行状态的情况下，控制第二电流传感器不工作。示例性的，第一控制器可以向第二电流传感器发送第一控制信号，该第一控制信号用于指示第二电流传感器不工作。
可选的，当第一控制器和第二控制器是两个独立的控制器，且第一控制器和第二控制器分别用于控制第一电流传感器和第二电流传感器的情况下，第一电流传感器和第二电流传感器之间的工作切换可以是由第一控制器控制的，具体的，第一控制器还用于，在第一电流传感器处于运行状态的情况下，向第二控制器发送第二控制信号，第二控制信号用于指示第二电流传感器不工作，第二控制器用于根据第二控制信号控制第二电流传感器不工作。
可选的，第二电流传感器由同一个电池包中的电池模组供电。此时，不需要外部电源即可实现对地短路故障检测和分断保护功能，可以保证在储能系统不与交流电网连接或者与储能系统连接的交流电网没电的情况下，仍然能够检测电芯对地短路故障。
可选的，当第二控制器集成在第二电流传感器中时，第二控制器也可以由同一个电池包中的电池模组供电，即，采用相同的电池模组同时为第二电流传感器和第二控制器供电。如此，能够保证在储能系统不与交流电网连接或者与储能系统连接的交流电网没电的情况下，仍然能够检测电芯对地短路故障，并及时进行分断保护。
可选的，第一电流传感器可以采用霍尔传感器，隧道磁电阻传感器(Tunnel Magneto Resistance，TMR)，各向异性磁阻传感器(Anisotropic Magneto Resistive，AMR)，巨磁阻传感器(Giant Magneto Resistive，GMR)中的任意一种。
第二方面，本申请提供了一种储能系统，储能系统可以包括至少一个储能单元簇和直流/交流变换器，其中，储能单元簇中包括至少两个如第一方面任一项所述的电池包，至少两个电池包串联连接，储能单元簇通过直流/交流变换器连接至交流电网或负载。
可选的，上述储能单元簇还包括辅源，辅源的两端分别与上述储能单元簇的正输出端和负输出端连接。
可选的，上述第一电流传感器由上述辅源供电。
可选的，当第一控制器集成在第一电流传感器中时，上述第一控制器由上述辅源供电。
当储能系统与交流电网连接，且交流电网有电的情况下，簇级辅源也处于有电的状态，用簇级辅源给第一电流传感器和/或第一控制器供电，能够确保第一电流传感器和/或第一控制器的正常运行。
第二方面中的任一可能设计可以达到的技术效果，请参照上述第一方面中的任一可能设计可以达到的技术效果，这里不再重复赘述。本申请的这些方面或其它方面在以下实施例的描述中会更加简明易懂。
附图说明
为了更清楚地说明本申请实施例或背景技术中的技术方案，下面将对本申请实施例或背景技术中所需要使用的附图进行说明。
图1为工商业场景中一个电池簇的结构示意图；
图2为电站场景中一个电池簇的结构示意图；
图3为本申请实施例提供的一个储能系统的结构示意图；
图4为本申请实施例提供的另一个储能系统的结构示意图；
图5为本申请实施例提供的另一个储能系统的结构示意图；
图6为本申请实施例提供的另一个储能系统的结构示意图；
图7为本申请实施例提供的一个储能单元簇的结构示意图；
图8为本申请实施例提供的一个储能系统在正常运行状态下的电流回路示意图；
图9为本申请实施例提供的一个储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图；
图10为本申请实施例提供的另一个储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图；
图11为本申请实施例提供的另一个储能单元簇的结构示意图；
图12为本申请实施例提供的另一个储能系统在正常运行状态下的电流回路示意图；
图13为本申请实施例提供的另一个储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图；
图14为本申请实施例提供的另一个储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图。
具体实施方式
为了使本申请的目的、技术方案和优点更加清楚，下面结合本发明实施例中的附图对本发明实施例进行描述。以下描述中，示出本发明实施例的具体方面或可使用本发明实施例的具体方面的附图。应理解，本发明实施例可在其它方面中使用，并可包括附图中未描绘的结构或逻辑变化。因此，以下详细描述不应以限制性的意义来理解，且本发明的范围由所附权利要求书界定。
需要说明的是，在本申请实施例的描述中，除非另有说明，“/”表示或的意思，例如，A/B可以表示A或B；本文中的“和/或”仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，在本申请实施例的描述中，“多个”是指两个或多于两个，“至少一个”和“一个或多个”是指一个、两个或两个以上。单数表达形式“一个”“一种”“所述”“上述”“该”和“这一”旨在也包括例如“一个或多个”这种表达形式，除非其上下文中明确地有相反指示。
在本说明书中描述的参考“一个实施例”或“一些实施例”等意味着在本申请的一个或多个实施例中包括结合该实施例描述的特定特征、结构或特点。由此，在本说明书中的不同之处出现的语句“在一个实施例中”、“在一些实施例中”、“在其他一些实施例中”、“在另外一些实施例中”等不是必然都参考相同的实施例，而是意味着“一个或多个但不是所有的实施例”，除非是以其他方式另外特别强调。术语“包括”、“包含”、“具有”及它们的变形都意味着“包括但不限于”，除非是以其他方式另外特别强调。
本申请实施例的描述中，术语“上”、“下”、“左”、“右”、“垂直”、“水平”等指示的方位或位置关系为相对于附图中的部件示意放置的方位或位置来定义的，应当理解到，这些方向性术语是相对的概念，它们用于相对于的描述和澄清，而不是指示或暗示所指的装置或元器件必须具有的特定的方位、或以特定的方位构造和操作，其可以根据附图中部件所放置的方位的变化而相应地发生变化，因此不能理解为对本申请的限定。
本申请实施例中以同一附图标记表示同一组成部分或同一零部件。另外，附图中各个零部件并非按比例绘制，图中示出的零部件的尺寸和大小仅为示例性的，不应理解为对本申请的限定。
在本申请中，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”、“固定”、“连通”、“配置”等术语应做广义理解，例如，可以是固定连接，可以使可拆卸连接、可拆卸固定、也可以是一体连接等；可以是机械连接，也可以是电连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个器件内部的连通或两个器件的相互作用关系，除非另有明确的限定。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请中的具体含义。
需要说明的是，当器件被称为“固定于”或“设置于”或“配置于”另一个器件，它可以直接在另一个器件上或者也可以存在居中的器件。当一个器件被认为是“连接”另一个器件，它可以是直接连接到另一个器件或者可能同时存在居中器件。本文所使用的术语“垂直的”、“水平的”、“上”、“下”、“左”、“右”以及类似的表述只是为了说明的目的，并不表示是唯一的实施方式。
本发明的实施方式部分使用的术语仅用于对本发明的具体实施例进行解释，而非旨在限定本发明。
目前，随着新能源占比逐步提升，为解决大规模光伏和风力发电等发电间歇不稳定问题，电池储能系统的配置日益重要，且储能系统的配置占比也日益提升。受限于电芯及电池模组加工颗粒度的大小限制，电池储能系统一般由多个电池模组串联后再并联组成，多个电池模组放置在一起容易导致一些安全隐患。并且，由于电芯来料、加工制程等过程中会不可避免的造成某些电芯存在一定的缺陷，这些缺陷可能会导致这些电芯在使用过程中发生例如漏液失效等异常情况，这些异常情况会导致电芯发生对地短路故障。因此，如何设计安全的保护方案，做到即使电芯发生对地短路故障等情况时，故障仍不会扩散尤为关键。
在储能系统中，若单个电池包中的电芯发生对地短路故障，其对整个储能系统的运行影响不大，但如果发生两个及以上电池包中的电芯发生对地短路故障，则容易由于电压击穿导致起火风险，严重危害整个储能系统的安全运行。
针对储能系统潜在的故障可能性，即，电池包中的电芯不可避免的存在发生对地短路故障的可能性，现有技术中采取多种方式保障储能系统的安全运行。
例如，现有技术中通常在电池包内配置普通熔丝，簇控制盒中配置簇级高压普通熔丝，电池包中的普通熔丝和簇控制盒中的高压普通熔丝在通过的电流大于阈值的情况下会熔断，进而对功率变换器等部件失效导致的差模故障进行分断保护。
另外，簇控制盒中还配置有簇级绝缘阻抗检测功能和簇级开关，在发生电芯漏液、异物进入PACK等情况导致电芯对地绝缘失效时，绝缘阻抗检测电路可以在系统上电前识别绝缘阻抗异常，并控制簇级开关分断，以进行分断保护，但在系统上电运行的过程中，绝缘阻抗检测电路无法识别异常，因此在系统上电运行的过程中，无法起到有效的保护作用。
除此之外，簇控制盒中还配置有剩余电流动作保护器(residual current operated protective device，RCD)。图1为工商业场景中一个电池簇的结构示意图，参见图1，对于工商业场景而言，功率变换器的交流侧接地。因此，当发生电池包单点对地绝缘失效(也即，单个电池包中的电芯发生对地短路故障)时，簇级RCD可以检测到故障电流，触发簇级开关进行分断保护，但当同一个电池簇内有两个或者两个以上电池包中的电芯发生对地短路故障时，即使簇级开关分断，电池簇内发生对地短路故障的两个电池包之间仍然可能由于电压击穿导致起火风险，因此，在同一个电池簇内有两个或者两个以上电池包内的电芯发生对地短路故障的情况下，断开簇级开关并不能有效防止起火等危险的发生。图2为电站场景中一个电池簇的结构示意图，参见图2，对于电站场景而言，功率变换器的交流侧不接地。因此，无论发生电池包单点对地短路故障还是电池包多点对地短路故障(也即，多个电池包中的电芯发生对地短路故障)时，簇级RCD均无法检测到故障电流，无法触发簇级开关进行分断保护。此外，对于储能系统没有上电的场景(如运输和存储场景)，簇级RCD更无法检测PACK内的电芯对地短路故障，也无法触发分断保护。
针对上述问题，本申请提供了一种在电池簇内两个及两个以上电池包中的电芯发生对地短路故障的情况下，能够快速切断故障，确保储能系统安全运行的电池包及储能系统。
首先，介绍本申请实施例提供的储能系统。图3-图6为本申请实施例提供的四种储能系统的结构示意图，参见图3-图6，本申请实施例提供的储能系统中包括一个或者多个储能单元簇(图中示出了两个储能单元簇，电池簇1和电池簇2)，一个储能单元簇可包括至少两个电池包(图中每一个电池簇包括N个电池包)，且各个电池包相互串联。换句话说，一个储能单元簇可由至少两个电池包串联组成。电池包的内部结构将在下文进行详细的介绍。
需要说明的是，本申请实施例提供的储能系统涉及多层结构，第一层称为储能系统或者电池储能系统，第二层称为储能单元簇或者电池簇，第三层称为电池包或者PACK，第四层称为电池模组。上述同一层结构的不同名称在本申请实施例中的含义相同，均用于指代这特定层结构，本申请实施例不进行区分。电池模组可以由多个电芯串联而成，电池包可以包括电池模组、电池管理单元(battery management unit，BMU)和优化器，电池簇可以包括多个串联的电池包，储能系统可以包括多个并联的电池簇。如图3-图6所示，在本申请提供的储能系统中，一个或者多个储能单元簇可以以电池簇1至和电池簇2为例进行说明，其中电池簇1可由PACK11至PACK1n串联组成，电池簇2可由PACK21至PACK2n串联组成，n为整数。
在一种可能的实施方式中，储能系统中各电池簇可通过直流(direct current，DC)/直流变换器(DC/DC变换器)耦合到直流母线，一个电池簇通过一个DC/DC变换器耦合到直流母线，如图3所示，电池簇1可通过变换器DC/DC1耦合到直流母线，电池簇2可通过变换器DC/DC2耦合到直流母线。各电池簇通过DC/DC变换器耦合到直流母线以实现多个电池簇的简单并联扩展，可增加储能系统的储能容量，通过DC/DC变换器还可实现单个电池簇的能量的灵活控制，以及异常工况下单个电池簇的快速切换，适用性强。多个电池簇并联之后，可以共用一个直流/交流(alternating current，AC)逆变器(DC/AC变换器)将直流电转化为交流电，并与交流电网之间进行能量交换。
这里，DC/DC变换器可以为双向DC/DC变换器，双向DC/DC变换器的电路拓扑可以为隔离型电路拓扑，也可为非隔离型电路拓扑，双向DC/DC变换器的升压比由直流母线的电压和电池簇的端口电压确定。以电池簇1为例，由于电池的端口电压随电池的储能容量变化，电池簇1的端口电压随着电池簇1中串联的电池包的数量变化，电池簇1中串联的电池包的数量变化较大时也将使得电池簇1的端口电压变化较大。例如，假设电池包的端口电压为50V，当电池簇1中串联2个电池包时，电池簇1的端口电压为100V，当电池簇1中串联30个电池包时，电池簇1的端口电压为1500V，即低压系统的上限电压，因此电池簇1的端口电压可为一个宽范围的输出电压，比如100V～1500V。为了匹配电池簇1的端口电压变化范围，变换器DC/DC1通常可采用非隔离型电路拓扑实现，并可设计为具有宽范围的输入/输出能力的变换器，从而可灵活适配不同的输入/输出电压。这里，双向DC/DC变换器(包括变换器DC/DC1和DC/DC2等)的电路拓扑可选用升压电路(boost circuit)、飞跨电容升压电路(boost circuit boost circuit)、飞跨电容多电平电路(flying capacitor multilevel circuit)、正负对称三电平升压电路(three-level boost circuit)，四管升降压电路(four-switch buck-boost circuit)等，具体可根据实际应用场景需求确定。变换器DC/DC1的升压比可由直流母线的电压和电池簇1的端口电压确定，具体可根据实际应用场景确定。
在一些可行的实施方式中，为了实现单个电池簇的管理，可针对各个电池簇增加集中监控系统(battery control unit，BCU)，其中，一个电池簇对应一个集中监控系统BCU。比如电池簇1可对应变换器DC/DC1中的集中监控系统BCU1，电池簇2可对应变换器DC/DC2中的集中监控系统BCU2。各电池簇的集中监控系统可通过控制总线连接电池簇中各电池包，集中监控系统可与电池簇中各电池包进行信息的实时交互，可实现对各电池簇中电池包的实时、统一监控，从而可实现对储能系统的灵活控制，适用性强。可选的，集中监控系统BCU作为独立放置的电路模块时，单个电池簇所对应的集中监控系统跟DC/DC变换器中的控制器实现信息交互，同时集中监控系统通过控制总线连接该电池簇中各个电池包。具体实现中，集中监控系统BCU和电池包的信息交互方式还可以是无线通信、直流电力载波通信等等，具体可根据实际应用场景确定，操作灵活，适用性高。可选的，单个电池簇的集中监控系统BCU作为单独的电路板或者电路模块集成在该电池簇所连接的DC/DC变换器时，可简化储能系统的系统结构，同时由于单个电池簇通常与DC/DC变换器近距离安装，因此将单个电池簇的集中监控系统集成在DC/DC变换器中，有利于控制总线的连接。
可选的，在一些可行的实施方式中，为了实现电池包的状态监测和控制，各电池簇的电池包中可增加一个BMU，该BMU中可包含模组电池管理系统(module battery management system，mBMS)以及相应的采样控制模块、通信模块、供电模块、开关桥臂的驱动控制电路等，用于实现电池包中各个储能元件组(即各个电池组)的状态检测和控制。电池簇的集中监控系统BCU与电池包中的电池管理单元BMS通信连接，共同实现对电池包的状态检测和控制。
在一种可能的实现方式中，也可以给每个电池簇单独配置DC/AC变换器，即，多个电池簇不共用DC/AC变换器，电池簇直接输出变换后的交流电到交流电网。如图4所示，电池簇1可通过变换器DC/DC1和变换器DC/AC1耦合到交流电网，电池簇2可通过变换器DC/DC2和变换器DC/AC2耦合到交流电网。各电池簇通过DC/DC变换器和DC/AC变换器耦合到交流电网以实现多个电池簇的简单并联扩展，可增加储能系统的储能容量，并与交流电网之间进行能量交换。
在一种可能的实现方式中，也可以给每个电池簇配置一个簇控制盒，用于对单个电池簇进行统一控制。簇控制盒内可以设置簇级熔丝、簇级绝缘阻抗检测、簇级开关等器件，实现电池簇级的管理和保护。如图5所示，电池簇1可通过簇控制盒1耦合到直流母线，电池簇2可通过簇控制盒2耦合到直流母线。各电池簇通过簇控制盒耦合到直流母线以实现多个电池簇的简单并联扩展，可增加储能系统的储能容量。多个电池簇并联之后，可以共用一个DC/AC变换器将直流电转化为交流电，并与交流电网之间进行能量交换。
在一种可能的实现方式中，也可以在给每个电池簇配置一个簇控制盒的基础上，再单独给每个电池簇配置DC/AC变换器，即，多个电池簇不共用DC/AC变换器，电池簇直接输出变换后的交流电到交流电网。如图6所示，电池簇1经过簇控制盒1后输出的电能可通过变换器DC/AC1耦合到交流电网，电池簇2经过簇控制盒2后输出的电能可通过变换器DC/AC2耦合到交流电网。各电池簇通过DC/AC变换器耦合到交流电网以实现多个电池簇的简单并联扩展，可增加储能系统的储能容量，并与交流电网之间进行能量交换。
接下来，介绍本申请实施例提供的电池包的内部结构。图7为本申请实施例提供的一个储能单元簇的结构示意图，该储能单元簇包括多个串联的电池包和一个簇控制盒。如图7所示，本申请实施例中每个电池包均包括电池模组，分断器件(图7中以开关为例)，第一电流传感器(图7中以RCD为例)和第一控制器(图7中未示出)。示例性的，如图7所示的储能单元簇包括PACK1…PACKn-1、PACKn，其中PACK1包括电池模组1，分断器件1和RCD1，PACKn包括电池模组n，分断器件n和RCDn。
其中，电池模组中包括多个单体电芯，多个单体电芯之间串联连接，以扩展电池包的容量。应当理解，可以根据实际需求灵活设置电池模组中单体电芯的数量。
其中，分断器件与电池模组串联连接，图7中分断器件串联在电池模组的负极，应当理解，分断器件也可以串联在电池模组的正极，本申请实施例对分断器件与电池模组的相对位置不进行限定。本申请实施例中的分断器件为可控分断器件，即，分断器件在控制信号的控制下进行分断，进而断开该电池包中的电流通路。示例性的，分断器件可以采用开关、爆炸熔丝、接触器、继电器、断路器、绝缘栅双极型晶体管(Insulated Gate Bipolar Transistor,IGBT)、或者金属-氧化物半导体场效应晶体管(Metal Oxide Semiconductor Field Effect Transistor,MOSFET)。当分断器件采用开关时，开关可以在控制信号的控制下断开，进而断开电池包中的电流通路。当分断器件采用爆炸熔丝时，爆炸熔丝可以在控制信号的控制下断开，进而断开电池包中的电流通路。应当理解，任何能够根据控制信号进行分断的器件都可以作为本申请实施例中的可控分断器件，且可以根据实际需求灵活选择可控分断器件。
其中，第一电流传感器的第一端连接该电池包的正输出端，第一电流传感器的第二端连接该电池包的负输出端，从而检测该电池包的正输出端和负输出端之间的电流差。在一种可能的是实现方式中，第一电流传感器可以是一个用于检测电流差的器件，在另一种可能的实现方式中，第一电流传感器也可以是一个用于检测电流差的电路。示例性的，第一电流传感器可以为剩余电流动作保护器(residual current operated protective device，RCD)。应当理解，任何能够通过连接在电池包的两端并获取两端之间的电流差的传感器都可以作为本申请实施例中的第一电流传感器，且可以根据实际需求灵活选择第一电流传感器。
其中，第一控制器用于在该电池包的正输出端和负输出端之间的电流差大于第一阈值的情况下控制上述分断器件断开，也即，第一控制器永远在第一电流传感器检测到的电流差大于第一阈值的情况下控制上述分断器件断开。
在一种可能的实现方式中，第一控制器与第一电流传感器可以集成在一块电路板上，换言之，第一电流传感器可以是一个具有逻辑判断功能和控制功能的智能电流传感器。在另一种可能的实现方式中，第一控制器可以独立于第一电流传感器设置，第一控制器可以是单独的控制器，也可以集成在在电池包中的其他器件中。在另一种可能的实现方式中，第一控制器也可以是电池包中的BMS。
在一种可能的实现方式中，本申请实施例提供的储能单元簇可以不设置簇控制盒。在另一种可能的实现方式中，本申请实施例提供的储能单元侧也可以设置簇控制盒，簇控制盒中可以设置簇级熔丝，或者簇级开关，或者簇级绝缘阻抗检测电路。示例性的，簇控制盒中可以设置RCD对电池簇的正输出端盒负输出端之间的电流差进行检测，进一步提升储能系统的安全性，也可以基于成本考虑，在电池包中设置第一电流传感器之后，不再在簇控制盒中设置RCD。
接下来，对本申请实施例提供的如图7所示的储能单元簇的工作原理进行说明。
图8为如图7所示的储能系统在正常运行状态下的电流回路示意图，如图8所示，在储能系统运行正常的情况下，储能单元簇内的一个电池包的两端的电流应该是大致相等的，也即，在储能系统运行正常的情况下，电池包的两端不存在电流差，或者仅存在微小的电流差。因此，通过合理设置第一阈值，当储能系统运行正常时，第一电流传感器检测到的电流差不会大于第一阈值，分断器件处于闭合状态。
图9为如图7所示的储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图，如图9所示，电池包1和电池包n-1中的电芯均发生对地短路故障。此时，由于存在两个接地点，相当于多个电芯在没有负载的情况下串联在一起，由于多个电芯串联在一起的电压很大，极易由于电压击穿导致起火危险。此时，由于储能单元簇中存在两个电流回路，发生对地短路故障的两个电池包的两端的电流大小不相同，即，发生对地短路故障的两个电池包的两端均存在电流差。在本申请实施例中，当发生对地短路故障的电池包内的第一电流传感器检测到的电流差大于第一阈值时，控制同一个电池包内的分断器件断开，能够断开储能单元簇内的故障回路。以图9为例，分断器件串联在电池模组的负极，当PACK1和PACKn-1中的电芯发生对地短路故障时，PACK1的正输出端和负输出端之间存在电流差，PACK1中的第一电流传感器检测到的电流差大于第一阈值，进而触发PACK1中的第一控制器控制分断器件1断开。分断器件1断开可以断开图9中的故障回路避免由于电压击穿导致的起火危险。
图10为本申请实施例提供的另一个储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图。图10与图9的区别在于图9中的分断器件串联在电池模组的负极，而图10中的分断器件串联在电池模组的正极。如图10所示，当PACK1和PACKn-1中的电芯发生对地短路故障时，PACK n-1的正输出端和负输出端之间存在电流差，PACK n-1中的第一电流传感器检测到的电流差大于第一阈值，进而触发PACK n-1中的第一控制器控制分断器件n-1断开。分断器件n-1断开可以断开图10中的故障回路避免由于电压击穿导致的起火危险。可见，无论是将分断器件串联在电池模组的正极还是将分断器件串联在电池模组的负极，均可以起到分断保护作用，本申请实施例对此不进行限定。
图11为本申请实施例提供的另一个储能单元簇的结构示意图，如图11所示，在一种可能的实现方式中，本申请实施例所提供的电池包还包括第二电流传感器(图11中以TMR为例)和第二控制器(图11中未示出)，图11中的分断器件以爆炸熔丝为例。示例性的，如图11所示的储能单元簇包括PACK1…PACKn-1、PACKn，其中PACK1包括电池模组1，分断器件1，TMR1和RCD1，PACKn包括电池模组n，分断器件n，TMRn和RCDn。
其中，第二电流传感器与电池包中的电池模组和分断器件均串联连接，图11中第二电流传感器串联在电池模组的负极和分断器件之间，应当理解，第二电流传感器还可以串联在电池模组的正极。第二电流传感器用于检测所串联的电路中通过的电流的大小。在一种可能的是实现方式中，第二电流传感器可以是一个用于检测电流的器件，在另一种可能的实现方式中，第二电流传感器也可以是一个用于检测电流的电路。示例性的，第一电流传感器可以为霍尔传感器，隧道磁电阻传感器(Tunnel Magneto Resistance，TMR)，各向异性磁阻传感器(Anisotropic Magneto Resistive，AMR)，巨磁阻传感器(Giant Magneto Resistive，GMR)中的任意一种。应当理解，上述举例仅仅是示例性的，任何能够通过串联在电路中并检测通过的电流的传感器都可以作为本申请实施例中的第二电流传感器，且可以根据实际需求灵活选择第二电流传感器。
需要说明的是，第二电流传感器和分断器件需要串联在电池模组的同一侧，才能够实现对电芯对地短路故障的检测和分断保护功能。示例性的，第二电流传感器和分断器件可以均串联在电池模组的负极，第二电流传感器和分断器件也可以均串联在电池模组的正极。本申请实施例对第二电流传感器和分断器件之间的相对位置关系不做限定。示例性的，在一种可能的实现方式中，TMR的一端与电池模组的正输出端连接，TMR的另一端与分断器件的一端连接，分断器件的另一端与电池包的正输出端连接。在另一种可能的实现方式中，分断器件的一端与电池模组的正输出端连接，分断器件的另一端与TMR的一端连接，TMR的另一端与电池包的正输出端连接。在另一种可能的实现方式中，TMR的一端与电池模组的负输出端连接，TMR的另一端与分断器件的一端连接，分断器件的另一端与电池包的负输出端连接。在另一种可能的实现方式中，分断器件的一端与电池模组的负输出端连接，分断器件的另一端与TMR的一端连接，TMR的另一端与电池包的负输出端连接。
其中，第二控制器用于在上述第二电流传感器检测到的电流大于第二阈值的情况下控制电池包中的分断器件断开。
在一种可能的实现方式中，第二控制器与第二电流传感器集成在一块电路板上，换言之，第二电流传感器可以是一个具有逻辑判断功能和控制功能的智能电流传感器。在另一种可能的实现方式中，第二控制器可以独立于第二电流传感器设置，第二控制器可以是单独的控制器，也可以集成在在电池包中的其他器件中。在另一种可能的实现方式中，第二控制器也可以是电池包中的BMS。
在一种可能的实现方式中，第一控制器和第二控制器可以是两个独立的控制器，例如，第一控制器和第二控制器可以分别集成在不同的器件或者电路板中。例如，第一控制器和第二控制器可以分别集成在第一电流控制器和第二电流控制器中。在一种可能的实现方式中，第一控制器和第二控制器可以是同一个控制器，即，用同一个控制器执行第一控制器和第二控制器的功能。例如，可以由BMS执行第一控制器和第二控制器的功能。
接下来，对本申请实施例提供的如图11所示的储能单元簇的工作原理进行说明。
图12为如图11所示的储能系统在正常运行状态下的电流回路示意图，如图12所示，在储能系统运行正常的情况下，储能单元簇内电流回路中的电流值大小是相对稳定的，通常仅存在微小的波动。因此，通过合理设置第二阈值，当储能系统运行正常时，第二电流传感器检测到的电流大小不会大于第二阈值，分断器件处于闭合状态。图13为如图11所示的储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图，如图13所示，电池包1和电池包n-1中的电芯均发生对地短路故障。此时，由于存在两个或者两个以上接地点，相当于多个电芯在没有负载的情况下串联在一起，此时，电流回路中的电流会激增，也就是说，相比于图12中的电流回路，图13中的电流回路中第二电流传感器中流经的电流会激增。在本申请实施例中，当电池包内的第二电流传感器检测到的电流大小超过第二阈值时，控制同一个电池包内的分断器件断开。如图13所示，当PACK1和PACKn-1-中的电芯发生对地短路故障时，PACK1中的第二电流传感器检测到的电流大小大于第二阈值，进而触发PACK1中的第二控制器控制分断器件1断开，分断器件1断开可以断开图13中的故障回路，进而避免由于电压击穿导致的起火危险。
图14为如图11所示的储能系统中两个或两个以上电池包发生对地短路故障情况下的电流回路示意图。图14与图13的区别在于图13中的第二电流传感器和分断器件串联在电池模组的负极，而图14中的第二电流传感器和分断器件串联在电池模组的正极。如图14所示，若将第二电流传感器和分断器件串联在电池模组的正极，则当PACK1和PACKn-1-中的电芯发生对地短路故障时，PACKn-1中的第二电流传感器检测到的电流大小大于第二阈值，进而触发PACKn-1中的第二控制器控制分断器件n-1断开，分断器件n-1断开可以断开图14中的故障回路，进而避免由于电压击穿导致的起火危险。可见，无论是将分断器件和第二电流传感器串联在电池模组的正极还是将分断器件和第二电流传感器串联在电池模组的负极，均可以起到分断保护作用，本申请实施例对此不进行限定。
应当理解，在一种可能的实现方式中，第二电流传感器可以独立于第一电流传感器存在，也即，在电池包中设置第二电流传感器和分断器件，通过第二电流传感器检测电芯对地短路故障，并控制分断器件断开，以实现故障条件下分断保护的效果。此时，只在电池包中设置一套故障检测和分断保护的逻辑。
在另一种可能的实现方式中，也可以在电池包中同时设置第一电流传感器和第二电流传感器，通过两套不同的控制逻辑检测电芯对地短路故障，能够更加可靠准确的检测到故障，及时进行分断保护，保障储能系统的安全运行。除此之外，当第一电流传感器或者第二电流传感器发生故障时，仍然可以通过另一套控制逻辑检测多个电池包对地短路的故障，进一步提高了系统的可靠性。
本申请实施例中还可以控制同一时刻下第一电流传感器和第二电流传感器中只有一个处于运行状态，以在提高系统可靠性的前提下节约电能。同理，当第一控制器和第二控制器为两个独立的控制器的情况下，也可以控制同一时刻下，第一控制器和第二控制器中只有一个处于运行状态，以在提高系统可靠性的前提下节约电能。需要说明的是，运行状态是指电流传感器或者控制器正常上电工作，实现检测或者控制功能，与运行状态对应的是非运行状态，非运行状态下，电流传感器或者控制器，不工作，也不耗电。
具体的，可以通过设置一个竞争信号来实现上述功能。本申请实施例中根据第一电流传感器的运行状态控制第二电流传感器的运行状态，具体的，当第一电流传感器处于运行状态时，控制第二电流传感器停止运行，当第一电流传感器处于非运行状态时，控制第二电流传感器运行。由于通常情况下，第一电流传感器的相比于第二电流传感器而言，检测电芯对地短路故障的精度更高，响应更快，效果更好，因此，设置第一电流传感器的优先级高于第二电流传感器的优先级，有利于提高电芯对地短路故障得检测效果。
在一种可能的实现方式中，当第一控制器的功能和第二控制器的功能由一个集中控制器(例如BMS)实现的情况下(这里称该集中控制器为第一控制器)，第一控制器还用于，在第一电流传感器处于运行状态的情况下，向第二电流传感器发送第一控制信号，该第一控制信号用于指示第二电流传感器不工作。示例性的，在第一时刻以前，第二电流传感器处于运行状态，实时检测通过的电流。第一时刻，第一电流传感器开始工作(例如，第一电流传感器开始工作的条件可以是第一电流传感器通电)，第一控制器在检测到第一电流传感器开始工作时，向第二传感器发送第一控制信号，第二传感器在接收到第一控制信号之后停止工作(第二传感器切换到非运行状态)。作为一种可能的实现方式，当第一电流传感器处于运行状态时，第一控制器持续的向第二电流传感器发送第一控制信号，或者第一控制器以预设的时间间隔向第二电流传感器发送第一控制信号，当第一控制器停止发送第一控制信号时，代表第一电流传感器停止工作(不再处于运行状态)，此时，第二传感器接收不到第一控制信号，重新开始工作。作为另一种可能的实现方式，第一控制器在发送第一控制信号之后停止发送第一控制信号，直至检测到第一电流传感器停止工作后，再发送第三控制信号给第二电流传感器，第三控制信号用于指示第二电流传感器运行。第二电流传感器在接收到第三控制信号之后重新开始工作。
在另一种可能的实现方式中，当第一控制器和第二控制器是两个独立的控制器，且第一控制器和第二控制器分别用于控制第一电流传感器和第二电流传感器的情况下，第一电流传感器和第二电流传感器之间的工作切换可以是由第一控制器控制的，具体的，第一控制器还用于，在第一电流传感器处于运行状态的情况下，向第二控制器发送第二控制信号，第二控制信号用于指示第二电流传感器不工作。示例性的，在第一时刻以前，第二电流传感器处于运行状态，实时检测通过的电流。第一时刻，第一电流传感器开始工作(例如，第一电流传感器开始工作的条件可以是第一电流传感器通电)，第一控制器在检测到第一电流传感器开始工作时，向第二控制器发送第一控制信号，第二控制器在接收到第一控制信号之后，控制第二电流传感器停止工作。作为一种可能的实现方式，当第一电流传感器处于运行状态时，第一控制器持续的向第二控制器发送第一控制信号，或者第一控制器以预设的时间间隔向第二控制器发送第一控制信号，当第一控制器停止发送第一控制信号时，代表第一电流传感器停止工作(不再处于运行状态)，此时，第二控制器接收不到第一控制信号，第二控制器控制第二电流传感器重新开始工作。作为另一种可能的实现方式，第一控制器在发送第一控制信号之后停止发送第一控制信号，直至检测到第一电流传感器停止工作后，再发送第三控制信号给第二控制器，第三控制信号用于指示第二电流传感器运行。第二控制器在接收到第三控制信号之后控制第二电流传感器重新开始工作。
在另一种可能的实现方式中，当第一控制器和第二控制器是两个独立的控制器，且第一控制器和第二控制器分别用于控制第一电流传感器和第二电流传感器的情况下，第一电流传感器和第二电流传感器之间的工作切换也可以是由第二控制器控制的。具体的，第二控制器还用于，在第一电流传感器处于运行状态的情况下，控制第二电流传感器不工作。此时，由第二控制器实时检测第一电流传感器的工作状态，并根据第一电流传感器的工作状态控制第二电流传感器的工作状态。
本申请实施例中还可以控制第一电流传感器和第二电流传感器在不同的情况下进行工作，以实现全时段对电芯故障进行检测。具体的，可以在与储能系统连接的交流电网有电时，通过第一电流传感器进行电芯对地短路故障检测，可以在与储能系统连接的交流电网没电，或者储能系统未与交流电网连接时，通过第二电流传感器进行电芯对地短路故障检测。如此，无论是在储能系统上电运行的状态下，还是储能系统运输、存储等不上电的状态下，均能够实现电芯对地短路故障检测和分断保护。
在一种可能的实现方式中，由于第一电流传感器通常耗电量较大，上述第一电流传感器可以由簇级辅源进行供电，进而在簇级辅源有电的情况下检测电芯对地短路故障，并控制分断器件进行分断保护。示例性的，如图11所示，簇级辅源可以设置在簇控制盒中，簇级辅源的第一端与储能单元簇的正输出端连接，簇级辅源的第二端与储能单元簇的负输出端连接。示例性的，簇级辅源可以由直流母线供电，或者，簇级辅源也可以由交流电网直接供电。
当第一控制器集成在第一电流传感器中时，第一控制器也可以由上述簇级辅源进行供电。当第一控制器集成在其他器件中，或者，当第一控制器是独立的控制器时，第一控制器也可以由上述簇级辅源进行供电。
当储能系统与交流电网连接，且交流电网有电的情况下，簇级辅源也处于有电的状态，用簇级辅源给第一电流传感器和/或第一控制器供电，能够确保第一电流传感器和/或第一控制器的正常运行。
在一种可能的实现方式中，为了保证在储能系统不与交流电网连接或者与储能系统连接的交流电网没电的情况下，仍然能够检测电芯对地短路故障，上述第二电流传感器可以由同一个电池包中的电池模组供电，进而不需要外部电源即可实现对地短路故障检测和分断保护功能。
当第二控制器集成在第二电流传感器中时，第二控制器也可以由同一个电池包中的电池模组供电，即，采用相同的电池模组同时为第二电流传感器和第二控制器供电。如此，能够保证在储能系统不与交流电网连接或者与储能系统连接的交流电网没电的情况下，仍然能够检测电芯对地短路故障，并及时进行分断保护。
显然，本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申请的精神和范围。这样，倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。

Claims (14)

  1. 一种具有分断保护功能的电池包，其特征在于，所述电池包中包括电池模组，分断器件，第一电流传感器和第一控制器；
    所述电池模组包括多个单体电芯；
    所述分断器件与所述电池模组串联连接，
    所述第一电流传感器的第一端连接所述电池包的正输出端，所述第一电流传感器的第二端连接所述电池包的负输出端，所述第一电流传感器用于检测所述正输出端和所述负输出端之间的电流差；
    所述第一控制器用于在所述电流差大于第一阈值的情况下控制所述分断器件断开。
  2. 如权利要求1所述的电池包，其特征在于，所述电池包中还包括第二电流传感器和第二控制器，所述第二电流传感器与所述电池包和所述分断器件串联连接，所述第二电流传感器用于检测通过的电流大小，所述第二控制器用于在所述第二电流传感器检测到的电流大于第二阈值的情况下控制所述分断器件断开。
  3. 如权利要求1或2所述的电池包，其特征在于，所述电池包中还包括第二电流传感器，所述第二电流传感器与所述电池模组和所述分断器件串联连接，所述第二电流传感器用于检测通过的电流大小，所述第一控制器用于在所述第二电流传感器检测到的电流大于第二阈值的情况下控制所述分断器件断开。
  4. 如权利要求2或3所述的电池包，其特征在于，所述第二电流传感器和所述分断器件均串联在所述电池包和所述电池包的正输出端之间，或者，所述第二电流传感器和所述分断器件均串联在所述电池包和所述电池包的负输出端之间。
  5. 如权利要求2-4任一项所述的电池包，其特征在于，所述第一电流传感器和所述第二电流传感器在同一时刻只有一个处于运行状态。
  6. 如权利要求2、4或5所述的电池包，其特征在于，所述第一控制器和所述第二控制器在同一时刻只有一个处于运行状态。
  7. 如权利要求2、4或5所述的电池包，其特征在于，所述第一控制器还用于，在所述第一电流传感器处于运行状态的情况下，向所述第二控制器发送第二控制信号，所述第二控制器还用于根据所述第二控制信号控制所述第二电流传感器不工作。
  8. 如权利要求2、4-7任一项所述的电池包，其特征在于，所述第二电流传感器或所述第二控制器由所述电池模组供电。
  9. 如权利要求3-5任一项所述的电池包，其特征在于，所述第一控制器还用于，在所述第一电流传感器处于运行状态的情况下，控制所述第二电流传感器。
  10. 如权利要求2-9任一项所述的电池包，其特征在于，所述第二电流传感器为以下至少一种：
    霍尔传感器，隧道磁电阻传感器TMR，各向异性磁阻传感器AMR，巨磁阻传感器GMR。
  11. 如权利要求1-10任一项所述的电池包，其特征在于，所述第一电流传感器为剩余电流动作保护器RCD。
  12. 如权利要求1-11任一项所述的电池包，其特征在于，所述分断器件为以下至少一种：
    开关、爆炸熔丝、接触器、继电器、断路器、绝缘栅双极型晶体管(IGBT)、金属-氧化物半导体场效应晶体管(MOS)。
  13. 一种具有分断保护功能的储能系统，其特征在于，所述储能系统包括至少一个储能单元簇和直流/交流(DC/AC)变换器，所述储能单元簇中包括至少两个如权利要求1-12任一项所述的电池包，所述至少两个电池包串联连接，所述储能单元簇通过所述DC/AC变换器连接至交流电网或负载。
  14. 如权利要求13所述的储能系统，其特征在于，所述储能单元簇还包括辅源，所述辅源的第一端与所述储能单元簇的正输出端连接，所述辅源的第二端与所述储能单元簇的负输出端连接；所述辅源用于为所述第一电流传感器或所述第一控制器供电。
PCT/CN2024/134887 2023-12-08 2024-11-27 一种具有分断保护功能的电池包及储能系统 Pending WO2025119053A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202311691834.7 2023-12-08
CN202311691834.7A CN117673517A (zh) 2023-12-08 2023-12-08 一种具有分断保护功能的电池包及储能系统

Publications (1)

Publication Number Publication Date
WO2025119053A1 true WO2025119053A1 (zh) 2025-06-12

Family

ID=90084318

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2024/134887 Pending WO2025119053A1 (zh) 2023-12-08 2024-11-27 一种具有分断保护功能的电池包及储能系统

Country Status (2)

Country Link
CN (1) CN117673517A (zh)
WO (1) WO2025119053A1 (zh)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117673517A (zh) * 2023-12-08 2024-03-08 华为数字能源技术有限公司 一种具有分断保护功能的电池包及储能系统
CN121642858A (zh) * 2024-09-10 2026-03-10 阳光电源股份有限公司 控制装置、计算机可读存储介质、电源系统、功率变换器及其保护方法
CN120511825B (zh) * 2025-07-18 2025-11-11 武汉船用电力推进装置研究所(中国船舶集团有限公司第七一二研究所) 一种支持热插拔的组合式储能装置及控制方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110265976A (zh) * 2019-06-20 2019-09-20 阳光电源股份有限公司 一种电池储能系统的联动保护电路及电池储能系统
WO2022156493A1 (zh) * 2021-01-25 2022-07-28 长城汽车股份有限公司 电池保护系统、电池保护方法、车辆、设备、程序和介质
CN115732867A (zh) * 2021-08-25 2023-03-03 宇通客车股份有限公司 一种电池系统短路保护电路及一种新能源车辆
CN116247765A (zh) * 2023-02-02 2023-06-09 华为数字能源技术有限公司 一种储能装置以及储能系统
CN116581712A (zh) * 2023-07-07 2023-08-11 深圳市首航新能源股份有限公司 一种电池簇及其储能系统
CN117673517A (zh) * 2023-12-08 2024-03-08 华为数字能源技术有限公司 一种具有分断保护功能的电池包及储能系统

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110265976A (zh) * 2019-06-20 2019-09-20 阳光电源股份有限公司 一种电池储能系统的联动保护电路及电池储能系统
WO2022156493A1 (zh) * 2021-01-25 2022-07-28 长城汽车股份有限公司 电池保护系统、电池保护方法、车辆、设备、程序和介质
CN115732867A (zh) * 2021-08-25 2023-03-03 宇通客车股份有限公司 一种电池系统短路保护电路及一种新能源车辆
CN116247765A (zh) * 2023-02-02 2023-06-09 华为数字能源技术有限公司 一种储能装置以及储能系统
CN116581712A (zh) * 2023-07-07 2023-08-11 深圳市首航新能源股份有限公司 一种电池簇及其储能系统
CN117673517A (zh) * 2023-12-08 2024-03-08 华为数字能源技术有限公司 一种具有分断保护功能的电池包及储能系统

Also Published As

Publication number Publication date
CN117673517A (zh) 2024-03-08

Similar Documents

Publication Publication Date Title
US9197056B2 (en) Solid state power control system for aircraft high voltage DC power distribution
WO2025119053A1 (zh) 一种具有分断保护功能的电池包及储能系统
EP3116118B1 (en) Power conversion device
CN106451610B (zh) 一种储能电池簇控制系统及其控制方法
CN102067421B (zh) 用于高压电力系统的电力设备
CN102870181A (zh) 高压dc断路器装置
CN110571847A (zh) 故障隔离装置、直流升压装置及逆变装置
CN102369644A (zh) 一种电池组防反接的控制电路及基站电源系统
JP7708910B2 (ja) 無瞬断電源供給制御装置及びその電源供給制御装置が適用されたｕｐｓモジュール
CN103248015A (zh) 储能变流器直流母线短路快速保护系统
WO2025118978A1 (zh) 电池模组、电池包和储能系统
CN106953295A (zh) 一种高压直流断路器控制系统及方法
CN114825417A (zh) 一种直流输电系统的控制电路、控制方法以及直流输电系统
CN117638821A (zh) 一种功率分配装置和充电桩
CN201918770U (zh) 一种直流充放电系统
CN201674275U (zh) 双电源自动切换回路
CN204696641U (zh) 一种用于保护高压电池用电系统的设备和具有该设备的车辆
CN107896102B (zh) 一种主通路串联固态开关的混合式开关
CN221150953U (zh) 一种串联dcdc短路保护电路和短路保护器
CN220754367U (zh) 一种充电系统和ac-dc模块
CN105932344A (zh) 一种可级联的动力电池组安全保护模块
KR102537206B1 (ko) 계통연계형 재생에너지 발전 시스템 및 그 동작방법
CN104092281B (zh) 一种交流双电源切换方法
CN207691416U (zh) 集约型直流融冰装置svg功率模块旁路结构
CN118983839B (zh) 供电系统

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24899693

Country of ref document: EP

Kind code of ref document: A1