Inter-cluster circulating flow suppression system and method

Abstract

The application relates to a kind of inter-cluster circulating current suppression system and method, the system reaches third preset threshold range when the maximum inter-cluster voltage difference in each battery cluster by processing unit, second control signal is transmitted to energy passive consumption circuit;Energy passive consumption circuit carries out energy consumption to high-voltage battery cluster in each battery cluster according to second control signal, so that the maximum inter-cluster voltage difference reaches second preset threshold range;Processing unit transmits first control signal to energy active transfer circuit when the maximum inter-cluster voltage difference reaches second preset threshold range;Energy active transfer circuit carries out energy transfer to each battery cluster according to first control signal, so that the maximum inter-cluster voltage difference reaches first preset threshold range;By controlling the active flow and passive absorption of inter-cluster energy, the voltage difference between battery clusters is quickly reached to reasonable interval, the circulating current generated by inhibiting inter-cluster voltage imbalance is realized, the circulating current suppression time is reduced, and the inter-cluster circulating current suppression efficiency and reliability are improved.

Description

Technical Field

[0001] This application relates to the field of inter-cluster electrical processing technology for energy storage, and in particular to an inter-cluster circulating current suppression system and method. Background Technology

[0002] With the development of battery technology, batteries are being widely used in more and more fields. For example, lithium-ion batteries are increasingly used in new energy ships. The energy supply method of new energy ships is to form a large energy storage system by connecting battery packs in series and / or parallel. However, the energy storage system contains a large number of battery cells. As the ship operates for a long time, the internal resistance, voltage, and remaining capacity of the batteries between the clusters will become inconsistent. When multiple clusters are connected in parallel, there will be a voltage difference between the clusters. When the voltage difference is large, a large circulating current will occur.

[0003] Currently, methods for suppressing inter-cluster circulating currents include, for example, controlling the power-on and power-off strategies between battery clusters to achieve energy transfer from high voltage to low voltage between clusters, keeping the voltage difference between each cluster within a reasonable range before power-on. However, this suppression method results in a long energy transfer time between battery clusters. Another method is to add a DC-DC module (DC-DC converter, a device that converts electrical energy from one voltage value to another in a DC circuit) to the output terminal of each battery cluster. By regulating the voltage through the converter, the output voltage of each cluster is kept consistent before power-on. However, this suppression method is costly and results in a large system size. Due to the nonlinearity of semiconductor device operation, it leads to reduced system efficiency under the same load. When multiple DC-DC modules are working, common-mode interference is generated, which seriously affects the stability of the DC source and also has a certain impact on the BMS (Battery Management System). When a short-circuit fault occurs on the grid side, a large current is generated at the converter terminal, which has a significant impact on the battery.

[0004] In the process of implementation, the inventors found that there are at least the following problems in the traditional technology: the existing inter-cluster circulation suppression methods have long suppression time and low efficiency, and the inter-cluster circulation suppression reliability is low. Summary of the Invention

[0005] Therefore, it is necessary to address the problems of long suppression time, low efficiency, and low reliability of existing inter-cluster circulation suppression methods, and to provide an inter-cluster circulation suppression system and method that can reduce the suppression time and improve the efficiency and reliability of inter-cluster circulation suppression.

[0006] In a first aspect, this application provides an inter-cluster circulation suppression system, comprising:

[0007] At least two battery clusters, each of which is used to supply power to the load via a DC bus;

[0008] An active energy transfer circuit includes at least two active energy transfer units, each of which is matched and connected to each battery cluster in a one-to-one manner. The active energy transfer circuit is configured to transfer energy to each battery cluster according to a received first control signal, so that the maximum inter-cluster voltage difference in each battery cluster reaches a first preset threshold range.

[0009] The passive energy consumption circuit includes at least two passive energy consumption units, each of which is matched and connected to a battery cluster in a one-to-one manner. The passive energy consumption circuit is configured to consume energy from the high-voltage battery clusters in each battery cluster according to a received second control signal, so that the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range. Any threshold in the second preset threshold range is greater than any threshold in the first preset threshold range. The high-voltage battery cluster is the battery cluster in each battery cluster whose voltage is greater than a preset voltage threshold.

[0010] The processing unit is configured to transmit a second control signal to the passive energy consumption circuit when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, and to transmit a first control signal to the active energy transfer circuit when the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range; any threshold of the third preset threshold range is greater than any threshold of the second preset threshold range.

[0011] Optionally, the inter-cluster circulating current suppression system also includes a pre-charging circuit; the pre-charging circuit includes at least two pre-charging units, each pre-charging unit being matched and connected to each battery cluster in a one-to-one manner; the pre-charging unit is configured to pre-charge the load according to the received third control signal;

[0012] The processing unit is also configured to transmit a third control signal to the pre-charge unit of the highest voltage battery cluster in each battery cluster when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, until the load pre-charging is completed, and then transmit a second control signal to the energy passive consumption circuit; and to transmit a third control signal to the pre-charge unit of the highest voltage battery cluster in each battery cluster when the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range, until the load pre-charging is completed, and then transmit a first control signal to the energy active transfer circuit.

[0013] Optionally, the processing unit is further configured to transmit a third control signal to the pre-charge unit of the highest voltage battery cluster in each battery cluster when the maximum inter-cluster voltage difference in each battery cluster reaches a fourth preset threshold range, until the load pre-charging is completed, and then transmit the third control signal to the pre-charge unit of the remaining battery clusters in each battery cluster in sequence; the maximum threshold of the fourth preset threshold range is greater than the maximum threshold of the first preset threshold range.

[0014] Optionally, the processing unit includes a processing chip, an MBMU domain management unit, a voltage acquisition unit, and at least two SBMU cluster management units; each SBMU cluster management unit is matched and connected to each battery cluster in a one-to-one correspondence; the voltage acquisition unit is configured to acquire the voltage of each battery cluster.

[0015] The MBMU domain management unit is connected to the voltage acquisition unit and each SBMU cluster management unit; the processing chip is connected to the MBMU domain management unit, voltage acquisition unit, active energy transfer circuit, and passive energy consumption circuit.

[0016] Optionally, the active energy transfer unit includes a first switching transistor, a second switching transistor, a first capacitor, a first resistor, and a first fuse;

[0017] The collector of the first switch is connected to the positive terminal of the corresponding battery cluster, the emitter of the first switch is connected to the collector of the second switch, the emitter of the second switch is connected to the DC bus, and the gates of the first switch and the second switch are respectively connected to the processing chip.

[0018] The positive terminal of the first capacitor is connected to the emitter of the first switching transistor, the negative terminal of the first capacitor is connected to the first end of the first resistor, the second end of the first resistor is connected to the first end of the first fuse, and the second end of the first fuse is connected to the negative terminal and the load of the corresponding battery cluster, respectively.

[0019] Optionally, the passive energy consumption unit includes a third switching transistor, a first diode, a second diode, a third diode, a second capacitor, a second resistor, a first inductor, and a second fuse;

[0020] The anode of the first diode is connected to the emitter of the third switch, the positive terminal of the second capacitor, and the first terminal of the inductor. The cathode of the first diode is connected to the negative terminal of the corresponding battery cluster, the cathode of the second diode, the first terminal of the second resistor, and the first terminal of the second fuse. The collector of the third switch is connected to the anode of the second diode and the second terminal of the second resistor. The gate of the third switch is connected to the processing chip. The second terminal of the second fuse is connected to the negative terminal of the second capacitor and the cathode of the third diode. The anode of the third diode is connected to the positive terminal of the second capacitor and the first terminal of the first inductor. The second terminal of the first inductor is connected to the corresponding pre-charge unit.

[0021] Optionally, the precharge unit includes a third resistor, a main relay, and a precharge relay;

[0022] The first end of the third resistor is connected to the first end of the pre-charge relay, the second end of the third resistor is connected to the first end of the main relay, and the second end of the pre-charge relay is connected to the second end of the main relay. The second end of the main relay is connected to the positive terminal of the corresponding battery cluster and the corresponding active energy transfer unit, respectively. The first end of the main relay is connected to the first inductor.

[0023] Optionally, the processing unit may also include an energy distribution unit that is connected to the MBMU domain management unit.

[0024] Secondly, this application provides a method for suppressing inter-cluster circulation, which includes the following steps;

[0025] When the maximum inter-cluster voltage difference in each battery cluster reaches the third preset threshold range, a second control signal is transmitted to the energy passive consumption circuit. The second control signal is used to instruct the energy passive consumption circuit to consume energy from the high-voltage battery clusters in each battery cluster so that the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range. The high-voltage battery cluster is the battery cluster in each battery cluster whose voltage is greater than the preset voltage threshold.

[0026] When the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range, a first control signal is transmitted to the active energy transfer circuit. The first control signal is used to instruct the active energy transfer circuit to transfer energy to each battery cluster so that the maximum inter-cluster voltage difference in each battery cluster reaches the first preset threshold range. Any threshold of the third preset threshold range is greater than any threshold of the second preset threshold range. Any threshold of the second preset threshold range is greater than any threshold of the first preset threshold range.

[0027] Optionally, when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, the step of transmitting a second control signal to the energy passive consumption circuit includes:

[0028] When the maximum inter-cluster voltage difference in each battery cluster reaches the third preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each battery cluster. After the load pre-charging is completed, a second control signal is transmitted to the energy passive consumption circuit. The third control signal is used to instruct the pre-charge unit to pre-charge the load.

[0029] Optionally, when the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range, the step of transmitting a first control signal to the active energy transfer circuit includes:

[0030] When the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each battery cluster. After the load pre-charging is completed, a first control signal is transmitted to the active energy transfer circuit. The third control signal is used to instruct the pre-charge unit to pre-charge the load.

[0031] Optionally, the inter-cluster circulation suppression method further includes the following steps:

[0032] When the maximum inter-cluster voltage difference in each battery cluster reaches the fourth preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each corresponding battery cluster. After the load pre-charging is completed, the third control signal is transmitted to the pre-charge unit of the remaining battery clusters in each corresponding battery cluster in sequence.

[0033] One of the above technical solutions has the following advantages and beneficial effects:

[0034] In the aforementioned inter-cluster circulating current suppression system, each battery cluster supplies power to the load via a DC bus. When the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, the processing unit transmits a second control signal to the passive energy consumption circuit. Based on the received second control signal, the passive energy consumption circuit consumes energy from the high-voltage battery clusters in each cluster to bring the maximum inter-cluster voltage difference to the second preset threshold range. When the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range, the processing unit transmits a first control signal to the active energy transfer circuit. Based on the received first control signal, the active energy transfer circuit transfers energy from each battery cluster to bring the maximum inter-cluster voltage difference to the first preset threshold range. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between battery clusters can be quickly brought to a reasonable range, suppressing circulating currents caused by voltage imbalances between battery clusters, while simultaneously reducing costs, increasing battery life, and decreasing circulating current suppression time. This application controls the active energy transfer circuit and the passive energy consumption circuit through the processing unit to achieve voltage balance between clusters. When the maximum inter-cluster voltage difference in each battery cluster falls within the second preset threshold range, the active inter-cluster energy transfer mode is adopted, thereby avoiding energy loss and improving energy utilization. When the maximum inter-cluster voltage difference in each battery cluster falls within the third preset threshold range, the passive energy consumption mode is adopted to reduce the number of battery charging cycles, improve battery life, and reduce energy transfer time, thereby improving the inter-cluster circulating current suppression efficiency and reliability. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the first structure of the inter-cluster circulation suppression system in this application embodiment.

[0036] Figure 2This is a schematic diagram of the second structure of the inter-cluster circulation suppression system in an embodiment of this application.

[0037] Figure 3 This is a schematic diagram of the third structure of the inter-cluster circulation suppression system in the embodiments of this application.

[0038] Figure 4 This is a schematic diagram of the structure of the active energy transfer unit in the embodiments of this application.

[0039] Figure 5 This is a schematic diagram of the structure of the passive energy consumption unit in the embodiments of this application.

[0040] Figure 6 This is a schematic diagram of the fourth structure of the inter-cluster circulation suppression system in the embodiments of this application.

[0041] Figure 7 This is a flowchart illustrating the inter-cluster circulation suppression method in the embodiments of this application.

[0042] Figure label:

[0043] Battery cluster 100; Active energy transfer circuit 200; Active energy transfer unit 210; Passive energy consumption circuit 300; Passive energy consumption unit 310; Processing unit 400; Processing chip 410; SBMU cluster management unit 420; MBMU domain management unit 430; Voltage acquisition unit 440; Energy distribution unit 450; DC bus 500; Pre-charge unit 610; Main relay S1; Pre-charge relay S2; First switch G1; Second switch G2; Third switch G3; First capacitor C1; Second capacitor C2; First resistor R1; Second resistor R2; Third resistor R3; First fuse F1; Second fuse F2; First diode D1; Second diode D2; Third diode D3; First inductor L1. Detailed Implementation

[0044] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0045] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0046] In addition, the term "multiple" should mean two or more.

[0047] Traditional methods for suppressing inter-cluster circulating currents include, for example, controlling the power-on and power-off strategies between battery clusters to achieve energy transfer from high voltage to low voltage, maintaining the voltage difference between each cluster within a reasonable range before power-on. However, this method results in a long energy transfer time between battery clusters. Another method involves adding a DC-DC converter (a device that converts electrical energy from one voltage value to another in a DC circuit) to the output of each battery cluster. The converter regulates the voltage to ensure consistency across clusters before power-on. However, this method is costly and results in a large system size. Due to the nonlinearity of semiconductor devices, system efficiency decreases under the same load. Multiple DC-DC modules operating simultaneously generate severe common-mode interference, significantly impacting the stability of the DC source and affecting the BMS (Battery Management System). Furthermore, a short-circuit fault on the grid side generates a large current at the converter, significantly impacting the battery system.

[0048] This application provides an inter-cluster circulating current suppression system and method for marine energy storage. By controlling the active flow and passive absorption of energy between battery clusters, it is possible to quickly bring the voltage difference between battery clusters to a reasonable range, thereby suppressing circulating currents caused by inter-cluster voltage imbalances. Simultaneously, it reduces costs, increases battery life, shortens circulating current suppression time, and improves the efficiency and reliability of inter-cluster circulating current suppression.

[0049] To address the problems of long suppression time, low efficiency, and low reliability of existing inter-cluster circulation suppression methods, in one embodiment, such as... Figure 1 As shown, an inter-cluster circulation suppression system is provided, which can be applied to ships. The inter-cluster circulation suppression system includes at least two battery clusters 100, an active energy transfer circuit 200, an active energy consumption circuit 300, and a processing unit 400.

[0050] Each battery cluster 100 is used to supply power to a load via a DC bus 500; the active energy transfer circuit 200 includes at least two active energy transfer units 210, each active energy transfer unit 210 being matched and connected to each battery cluster 100 in a one-to-one correspondence; the active energy transfer circuit 200 is configured to transfer energy to each battery cluster 100 according to a received first control signal, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches a first preset threshold range; the passive energy consumption circuit 300 includes at least two passive energy consumption units 310, each passive energy consumption unit 310 being matched and connected to each battery cluster 100 in a one-to-one correspondence; the passive energy consumption circuit 300 is configured to transfer energy to each battery cluster 100 according to a received second control signal. The high-voltage battery clusters 100 consume energy to make the maximum inter-cluster voltage difference in each battery cluster 100 reach a second preset threshold range; any threshold of the second preset threshold range is greater than any threshold of the first preset threshold range; the high-voltage battery cluster 100 is a battery cluster 100 whose voltage is greater than a preset voltage threshold; the processing unit 400 is configured to transmit a second control signal to the energy passive consumption circuit 300 when the maximum inter-cluster voltage difference in each battery cluster 100 reaches a third preset threshold range, and to transmit a first control signal to the energy active transfer circuit 200 when the maximum inter-cluster voltage difference in each battery cluster 100 reaches the second preset threshold range; any threshold of the third preset threshold range is greater than any threshold of the second preset threshold range.

[0051] The battery cluster 100 may include several individual battery cells. The battery cluster 100 refers to a battery assembly composed of individual battery cells connected in series, parallel, or series-parallel configurations, and capable of independent operation after connection to auxiliary facilities. The load may be, but is not limited to, an inverter, a motor control module, etc. The DC bus 500 can be used to electrically connect each battery cluster to the load side of a household inverter, motor control module, etc.

[0052] The active energy transfer circuit 200 may include a plurality of active energy transfer units 210. Each active energy transfer unit 210 is connected to each battery cluster 100 in a one-to-one correspondence. For example, if the system includes 5 battery clusters 100, then the number of active energy transfer units 210 is 5, that is, 5 active energy transfer units 210 are connected to 5 battery clusters 100 in a one-to-one correspondence. The active energy transfer circuit 200 is mainly used to transfer energy from the battery cluster 100 with higher voltage to the battery clusters 100 with lower voltage through the active energy transfer units 210 when the voltage difference between the battery clusters 100 is within a second preset threshold range, so that the voltage of each battery cluster 100 quickly reaches uniformity. For example, the second preset threshold range can be 5V≤V<10V.

[0053] The passive energy consumption circuit 300 may include a plurality of passive energy consumption units 310. Each passive energy consumption unit 310 is connected to each battery cluster 100 in a one-to-one correspondence. For example, if the system includes 5 battery clusters 100, then the number of corresponding passive energy consumption units 310 is 5, that is, 5 passive energy consumption units 310 are connected to 5 battery clusters 100 in a one-to-one correspondence. The passive energy consumption circuit 300 can be used to absorb and consume the energy of the battery cluster 100 with the higher battery voltage when the voltage difference between the battery clusters 100 is within a third preset threshold range, so that the voltage difference between the battery clusters 100 quickly reaches the second preset threshold range. For example, the third preset threshold range can be 10 ≤ V < 20V.

[0054] The processing unit 400 can be used to control the active energy transfer circuit 200 and the passive energy consumption circuit 300. Specifically, when the maximum inter-cluster voltage difference in each battery cluster 100 reaches a second preset threshold range, the processing unit 400 transmits a first control signal to the active energy transfer circuit 200. That is, when the voltage difference between the battery clusters 100 is not large, the processing unit 400 controls the active energy transfer circuit 200 to operate, adopting an active energy transfer method between the battery clusters 100 to achieve voltage balance between the battery clusters 100 and avoid energy loss, thereby improving energy utilization. When the maximum inter-cluster voltage difference in each battery cluster 100 reaches a third preset threshold range, the processing unit 400 transmits a second control signal to the passive energy consumption circuit 300. That is, when the voltage difference between the battery clusters 100 is large, the processing unit 400 controls the passive energy consumption circuit 300 to operate, adopting a passive energy consumption method between the battery clusters 100 to reduce the number of times the battery is repeatedly charged, thereby improving battery life and reducing energy transfer time.

[0055] The second control signal can be a PWM signal with a corresponding duty cycle, and the first control signal can also be a PWM signal with a corresponding duty cycle. The first preset threshold range can be, but is not limited to, 0 ≤ V < 1V. A high-voltage battery cluster 100 refers to the battery cluster 100 whose voltage is greater than a preset voltage threshold. For example, the preset voltage threshold can be the average voltage value among all battery clusters 100, then the high-voltage battery cluster 100 refers to the battery cluster 100 whose voltage is greater than the average voltage value.

[0056] Each battery cluster 100 is used to supply power to the load via the DC bus 500. When the maximum inter-cluster voltage difference in each battery cluster 100 reaches a third preset threshold range, i.e., when the voltage difference between battery clusters 100 is too large, the processing unit 400 transmits a second control signal to the energy passive consumption circuit 300. According to the received second control signal, the energy passive consumption circuit 300 consumes energy from the high-voltage battery clusters 100 in each battery cluster 100. The energy passive consumption unit 310 of the corresponding high-voltage battery cluster 100 consumes the electricity of the high-voltage battery cluster 100 in the form of heat, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches the second preset threshold range, and then the energy passive consumption circuit 300 disconnects. The processing unit 400... When the maximum inter-cluster voltage difference in each battery cluster 100 reaches the second preset threshold range, that is, when the voltage difference between battery clusters 100 is not large, a first control signal is transmitted to the active energy transfer circuit 200. The active energy transfer circuit 200 transfers energy to each battery cluster 100 according to the received first control signal, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches the first preset threshold range, thereby achieving voltage balance between battery clusters 100, avoiding energy loss, and improving energy utilization. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between battery clusters 100 can be quickly brought to a reasonable range, thereby suppressing the circulating current caused by voltage imbalance between battery clusters 100, while reducing costs, increasing battery life, and reducing the circulating current suppression time.

[0057] In the above embodiments, the processing unit 400 controls the active energy transfer circuit 200 and the passive energy consumption circuit 300 to achieve inter-cluster voltage balance. When the maximum inter-cluster voltage difference in each battery cluster 100 falls within the second preset threshold range, the active energy transfer method between clusters is adopted, thereby avoiding energy loss and improving energy utilization. When the maximum inter-cluster voltage difference in each battery cluster 100 falls within the third preset threshold range, the passive energy consumption method is adopted to reduce the number of battery charging cycles, improve battery life, and reduce energy transfer time, thereby improving the inter-cluster circulating current suppression efficiency and reliability.

[0058] To further reduce the circulating current suppression time in the battery system and improve the efficiency and reliability of inter-cluster circulating current suppression, in one example, such as Figure 2 As shown, the inter-cluster circulating current suppression system also includes a pre-charging circuit; the pre-charging circuit includes at least two pre-charging units 610, each pre-charging unit 610 being matched and connected to each battery cluster 100 in a one-to-one correspondence; the pre-charging unit 610 is configured to pre-charge the load according to the received third control signal.

[0059] The processing unit 400 is also configured to transmit a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100 when the maximum inter-cluster voltage difference in each battery cluster 100 reaches a third preset threshold range, until the load pre-charging is completed, and then transmit a second control signal to the energy passive consumption circuit 300; and to transmit a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100 when the maximum inter-cluster voltage difference in each battery cluster 100 reaches a second preset threshold range, until the load pre-charging is completed, and then transmit a first control signal to the energy active transfer circuit 200.

[0060] The pre-charging circuit may include several pre-charging units 610. Each pre-charging unit 610 is connected to each battery cluster 100 in a one-to-one correspondence. For example, if the system includes 5 battery clusters 100, then there are 5 pre-charging units 610, meaning that 5 pre-charging units 610 are connected to 5 battery clusters 100 in a one-to-one correspondence. The pre-charging unit 610 can be used to protect the main relay S1 contained in the pre-charging unit. The third control signal can be a level signal.

[0061] For example, the processing unit 400 can monitor the working status of the battery system in real time. After the battery system completes its self-test, it can obtain the voltage of each battery cluster 100, compare the highest voltage with the lowest voltage in each battery cluster 100, and obtain the maximum inter-cluster voltage difference in each battery cluster 100 based on the processing result. When the maximum inter-cluster voltage difference in each battery cluster 100 reaches the third preset threshold range, i.e., when the voltage difference between battery clusters 100 is too large, the processing unit 400 transmits a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100, so that the highest voltage battery cluster 100 conducts the pre-charge branch of the pre-charge unit 610 to pre-charge the load side connected to the DC bus 500 until the load pre-charging is completed, then disconnects the pre-charge branch of the pre-charge unit 610 and transmits a second control signal to the energy passive consumption circuit 300; the energy passive consumption circuit 300 consumes energy from the high voltage battery clusters 100 in each battery cluster 100 according to the received second control signal, and the energy passive consumption unit 310 of the corresponding high voltage battery cluster 100 consumes the electricity of the high voltage battery cluster 100 in the form of heat, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches the second preset threshold range, then the energy passive consumption circuit 300 disconnects.

[0062] When the maximum inter-cluster voltage difference in each battery cluster 100 reaches a second preset threshold range, i.e., when the voltage difference between battery clusters 100 is not large, the processing unit 400 transmits a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100. This causes the highest voltage battery cluster 100 to conduct the pre-charge branch of the pre-charge unit 610 to pre-charge the load side connected to the DC bus 500. Once the load pre-charging is complete, the pre-charge branch of the pre-charge unit 610 is disconnected, and a first control signal is transmitted to the energy active transfer circuit 200. The active energy transfer circuit 200 transfers energy to each battery cluster 100 according to the received first control signal, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches the first preset threshold range, thereby achieving voltage balance between battery clusters 100, avoiding energy loss, and improving energy utilization. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between battery clusters 100 can be quickly brought to a reasonable range, thereby suppressing circulating current caused by voltage imbalance between battery clusters 100, while reducing costs, increasing battery life, and reducing circulating current suppression time.

[0063] For example, the processing unit 400 is further configured to transmit a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100 when the maximum inter-cluster voltage difference in each battery cluster 100 reaches a fourth preset threshold range, until the load pre-charging is completed, and then transmit the third control signal to the pre-charge unit 610 of the remaining battery clusters 100 in each battery cluster 100 in sequence; the maximum threshold of the fourth preset threshold range is greater than the maximum threshold of the first preset threshold range.

[0064] The fourth preset threshold range can be 0 ≤ V < 5V. The processing unit 400 acquires the voltage of each battery cluster 100, compares the highest voltage with the lowest voltage in each battery cluster 100, and obtains the maximum inter-cluster voltage difference in each battery cluster 100 based on the processing result. When the maximum inter-cluster voltage difference in each battery cluster 100 reaches the fourth preset threshold range, that is, when the voltage difference between battery clusters 100 is small, the processing unit 400 transmits a third control signal to the pre-charge unit 610 of the battery cluster 100 with the highest voltage, so that the battery cluster 100 with the highest voltage will preferentially close the pre-charge branch of the pre-charge unit 610 to pre-charge the load side connected to the DC bus 500 until the load pre-charging is completed, and then closes the main circuit of the pre-charge unit 610, thereby completing the power-on of the battery cluster 100. Furthermore, a third control signal is transmitted sequentially to the pre-charge unit 610 of the remaining battery clusters 100 in each corresponding battery cluster 100, so that the remaining battery clusters 100 are pre-charged in sequence, the main circuit of the corresponding pre-charge unit 610 is closed, and the power-on process of the entire battery system is completed. Then, when the voltage difference between the battery clusters 100 is small, the pre-charge circuit is directly controlled to work, without the need to start the energy active transfer circuit 200 for energy transfer or the energy passive consumption circuit 300 for energy consumption, thereby improving energy utilization, battery life, and inter-cluster circulating current suppression efficiency and reliability.

[0065] In one embodiment, such as Figure 3 As shown, the processing unit 400 includes a processing chip 410, an MBMU (Master Battery Management Unit) domain management unit, a voltage acquisition unit 440, and at least two SBMU (Slave Battery Management Unit) cluster management units; each SBMU cluster management unit 420 is connected to each battery cluster 100 in a one-to-one correspondence; the voltage acquisition unit 440 is configured to acquire the voltage of each battery cluster 100. The MBMU domain management unit 430 is connected to the voltage acquisition unit 440 and each SBMU cluster management unit 420; the processing chip 410 is connected to the MBMU domain management unit 430, the voltage acquisition unit 440, the active energy transfer circuit 200, and the passive energy consumption circuit 300. For example, the processing unit 400 also includes an energy distribution unit 450 (i.e., an EMS unit) connected to the MBMU domain management unit 430.

[0066] The processing chip 410 can be, but is not limited to, a microcontroller, DSP, or FPGA. The MBMU domain management unit 430 can receive monitoring information from the battery cluster 100 obtained by the SBMU cluster management unit 420, and simultaneously communicate with the EMS (Battery Management System) unit for fault monitoring and functional control of the entire battery system. The SBMU cluster management unit 420 can receive cell status information collected by the VCMU (Voltage and Current Management System) and TCMU (Time Management System), and simultaneously perform fault monitoring and functional control within the battery cluster 100. The voltage acquisition unit 440 (HMU unit) refers to the high-voltage acquisition unit, which can be used to acquire the bus voltage of each battery cluster 100. The energy distribution unit 450 is responsible for the energy distribution management of various electrical modules on the ship and for implementing system protection functions.

[0067] For example, after receiving the EMS unit's ready signal, the MBMU domain management unit 430 begins a self-test. After the self-test is complete, the MBMU domain management unit 430 acquires the bus voltage of each battery cluster 100 through the voltage acquisition unit 440 (HMU unit) and uploads the acquired bus voltages of each battery cluster 100 to the MBMU domain management unit 430. The MBMU domain management unit 430 then compares the highest and lowest voltages in each battery cluster 100. Based on the processing results, the maximum inter-cluster voltage difference among the battery clusters 100 is transmitted to the processing chip 410. Then, when the maximum inter-cluster voltage difference in each battery cluster 100 reaches the third preset threshold range, that is, when the voltage difference between battery clusters 100 is too large, the processing chip 410 transmits a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100, so that the highest voltage battery cluster 100 conducts the pre-charge branch of the pre-charge unit 610 to pre-charge the load side connected to the DC bus 500 until the load pre-charging is completed, then disconnects the pre-charge branch of the pre-charge unit 610 and transmits a second control signal to the energy passive consumption circuit 300; the energy passive consumption circuit 300 consumes energy from the high voltage battery cluster 100 in each battery cluster 100 according to the received second control signal, and the energy passive consumption unit 310 of the corresponding high voltage battery cluster 100 consumes the electricity of the high voltage battery cluster 100 in the form of heat, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches the second preset threshold range, then the energy passive consumption circuit 300 disconnects.

[0068] When the maximum inter-cluster voltage difference in each battery cluster 100 reaches a second preset threshold range, i.e., when the voltage difference between battery clusters 100 is not large, the processing chip 410 transmits a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100. This causes the highest voltage battery cluster 100 to conduct the pre-charge branch of the pre-charge unit 610 to pre-charge the load side connected to the DC bus 500. Once the load pre-charging is complete, the pre-charge branch of the pre-charge unit 610 is disconnected, and a first control signal is transmitted to the energy active transfer circuit 200. The active energy transfer circuit 200 transfers energy to each battery cluster 100 according to the received first control signal, so that the maximum inter-cluster voltage difference in each battery cluster 100 reaches the first preset threshold range, thereby achieving voltage balance between battery clusters 100, avoiding energy loss, and improving energy utilization. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between battery clusters 100 can be quickly brought to a reasonable range, thereby suppressing circulating current caused by voltage imbalance between battery clusters 100, while reducing costs, increasing battery life, and reducing circulating current suppression time.

[0069] For example, the bus voltage of each battery cluster 100 is acquired by the voltage acquisition unit 440 (HMU unit) and transmitted to the processing chip 410. The processing chip 410 compares the highest and lowest voltages in each battery cluster 100. Based on the processing result, the maximum inter-cluster voltage difference in each battery cluster 100 is obtained. Then, based on the magnitude of the maximum inter-cluster voltage difference, the active energy transfer unit 210 and / or the passive energy consumption unit 310 can be controlled. This avoids energy loss, improves energy utilization, extends battery life, reduces energy transfer time, and thus improves inter-cluster circulating current suppression efficiency and reliability.

[0070] In one embodiment, such as Figure 6 As shown, the pre-charge unit 610 includes a third resistor R3, a main relay S1, and a pre-charge relay S2. The first end of the third resistor R3 is connected to the first end of the pre-charge relay S2, and the second end of the third resistor R3 is connected to the first end of the main relay S1. The second end of the pre-charge relay S2 is connected to the second end of the main relay S1. The second end of the main relay S1 is connected to the positive terminal of the corresponding battery cluster 100 and the corresponding active energy transfer unit 210, respectively. The first end of the main relay S1 is connected to the first inductor L1.

[0071] Among them, the third resistor R3 is the pre-charge resistor.

[0072] like Figure 4As shown, the active energy transfer unit 210 includes a first switch G1, a second switch G2, a first capacitor C1, a first resistor R1, and a first fuse F1. The collector of the first switch G1 is connected to the positive terminal of the corresponding battery cluster 100, the emitter of the first switch G1 is connected to the collector of the second switch G2, the emitter of the second switch G2 is connected to the DC bus 500, and the gates of the first switch G1 and the second switch G2 are respectively connected to the processing chip 410. The positive terminal of the first capacitor C1 is connected to the emitter of the first switch G1, the negative terminal of the first capacitor C1 is connected to the first terminal of the first resistor R1, the second terminal of the first resistor R1 is connected to the first terminal of the first fuse F1, and the second terminal of the first fuse F1 is connected to the negative terminal of the corresponding battery cluster 100 and the load.

[0073] In this circuit, both the first and second switching transistors, G1 and G2, can be IGBT devices. Using IGBT devices as the first and second switching transistors significantly reduces costs compared to the traditional approach of using a series DC-DC module to suppress inter-cluster circulating current. The first capacitor, C1, is a supercapacitor. The first resistor, R1, is a current-limiting resistor to prevent large short-circuit currents during charging of the first capacitor, C1, which could affect battery life. The first fuse, F1, provides short-circuit protection for the entire circuit.

[0074] The collector of the first switching transistor G1 is connected to the positive terminal of the corresponding battery cluster 100. The emitter of the first switching transistor G1 is connected to the collector of the second switching transistor G2. The emitter of the second switching transistor G2 is connected to the DC bus 500. The gates of the first switching transistor G1 and the second switching transistor G2 are respectively connected to the processing chip 410. The positive terminal of the first capacitor C1 is connected to the emitter of the first switching transistor G1. The negative terminal of the first capacitor C1 is connected to the first terminal of the first resistor R1. The second terminal of the first resistor R1 is connected to the first terminal of the first fuse F1. The second terminal of the first fuse F1 is connected to the negative terminal of the corresponding battery cluster 100 and the load, respectively.

[0075] When the maximum inter-cluster voltage difference in each battery cluster 100 reaches a second preset threshold range (e.g., 5V ≤ V < 10V), i.e., when the voltage difference between battery clusters 100 is not large, the processing chip 410 transmits a third control signal to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100. This causes the highest voltage battery cluster 100 to close the pre-charge relay S2 of the pre-charge unit 610, pre-charging the load side (equivalent capacitance in the figure) connected to the DC bus 500. Once the load pre-charging is complete, the pre-charge relay S2 of the pre-charge unit 610 is disconnected, and a first control signal is transmitted to the energy active transfer circuit 200.

[0076] The energy active transfer unit 210 of each battery cluster 100 circuit is connected in parallel. The conduction time of the first switch G1 is controlled by PWM. When the first switch G1 is on and the second switch G2 is off, the battery cluster 100 charges the first capacitor C1. When the voltage of the first capacitor C1 of each energy active transfer unit 210 is consistent with that of each parallel battery cluster 100, the first switch G1 is turned off and the second switch G2 is turned on, allowing the first capacitor C1 of each battery cluster 100 to be connected in parallel and perform energy transfer. When the voltage of the first capacitor C1 of each battery cluster 100 is consistent, the second switch G2 is turned off and the first switch G1 is turned on. Energy transfer between each battery cluster 100 and its first capacitor C1 continues until the voltage of each battery cluster 100 is consistent. This process is repeated until the voltage difference between each battery cluster 100 is consistent, at which point the first switch G1 and the second switch G2 of the energy transfer unit are turned off. After each battery cluster 100 has completed its pre-charging, the main relay S1 is closed, thereby completing the entire energy transfer process. At this time, the circuit of the active energy transfer unit 210 is in the open state, thus achieving voltage balance among the battery clusters 100, avoiding energy loss, and improving energy utilization. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between the battery clusters 100 can be quickly brought to a reasonable range, suppressing the circulating current caused by voltage imbalance among the battery clusters 100, while reducing costs, increasing battery life, and reducing the circulating current suppression time.

[0077] In one embodiment, such as Figure 5 As shown, the passive energy consumption unit 310 includes a third switch G3, a first diode D1, a second diode D2, a third diode D3, a second capacitor C2, a second resistor R2, a first inductor L1, and a second fuse F2.

[0078] The anode of the first diode D1 is connected to the emitter of the third switch G3, the positive terminal of the second capacitor C2, and the first terminal of the inductor. The cathode of the first diode D1 is connected to the negative terminal of the corresponding battery cluster 100, the cathode of the second diode D2, the first terminal of the second resistor R2, and the first terminal of the second fuse F2. The collector of the third switch G3 is connected to the anode of the second diode D2 and the second terminal of the second resistor R2. The gate of the third switch G3 is connected to the processing chip 410. The second terminal of the second fuse F2 is connected to the negative terminal of the second capacitor C2 and the cathode of the third diode D3. The anode of the third diode D3 is connected to the positive terminal of the second capacitor C2 and the first terminal of the first inductor L1. The second terminal of the first inductor L1 is connected to the corresponding pre-charge unit 610.

[0079] The third switch G3 can be an IGBT device. By using an IGBT as the first switch G1 and the second switch G2, compared to the traditional solution of using a series DC-DC module to suppress inter-cluster circulating current, the cost can be greatly reduced. The first diode D1, the second diode D2, and the third diode D3 are freewheeling diodes. The third diode D3 can be used to reduce the surge voltage generated when the third switch G3 is turned off. The second capacitor C2 is a filter capacitor; the second resistor R2 is a dissipation resistor. The second fuse F2 can be used to provide short-circuit protection for the entire circuit. The LC filter circuit formed by the first inductor L1 and the second capacitor C2 can be used to prevent harmonic interference caused by ground capacitance due to excessive line length. Simultaneously, the first inductor L1 protects components when current changes abruptly.

[0080] The anode of the first diode D1 is connected to the emitter of the third switch G3, the positive terminal of the second capacitor C2, and the first terminal of the inductor. The cathode of the first diode D1 is connected to the negative terminal of the corresponding battery cluster 100, the cathode of the second diode D2, the first terminal of the second resistor R2, and the first terminal of the second fuse F2. The collector of the third switch G3 is connected to the anode of the second diode D2 and the second terminal of the second resistor R2. The gate of the third switch G3 is connected to the processing chip 410. The second terminal of the second fuse F2 is connected to the negative terminal of the second capacitor C2 and the cathode of the third diode D3. The anode of the third diode D3 is connected to the positive terminal of the second capacitor C2 and the first terminal of the first inductor L1. The second terminal of the first inductor L1 is connected to the corresponding pre-charge unit 610. Thus, the maximum inter-cluster voltage difference of the processing chip 410 in each battery cluster 100 reaches the first... When the voltage difference between battery clusters 100 is large within a preset threshold range (e.g., 20V≤V), a third control signal is transmitted to the pre-charge unit 610 of the highest voltage battery cluster 100 in each battery cluster 100. This causes the highest voltage battery cluster 100 to close the pre-charge relay S2 of the pre-charge unit 610 and pre-charge the load side (equivalent capacitance in the figure) connected to the DC bus 500 until the load pre-charging is completed. Then, the pre-charge relay S2 of the pre-charge unit 610 is disconnected, and a second control signal is transmitted to the energy passive consumption circuit 300. Through the energy passive consumption unit 310 connected in series in the circuit of each battery cluster 100, the conduction time of the third switch G3 is controlled by PWM. The third switch G3 is turned on, so that the high voltage battery cluster 100 consumes the energy of the high voltage battery cluster 100 in the form of heat through the second resistor R2. At this time, the circuit of the active energy transfer unit 210 is in the open state. When the voltage difference between the battery clusters 100 falls within the second preset threshold range (5V≤V<10V), the circuit of the passive energy consumption unit 310 is disconnected, and the active energy transfer circuit 200 is controlled to enter the working state. When the voltage difference between each battery cluster 100 is consistent, the first switch G1 and the second switch G2 of the active energy transfer unit 210 are disconnected. Each battery cluster 100 undergoes pre-charging. After pre-charging is completed, the main relay S1 is closed, thus completing the entire power-on process. At this time, the circuit of the active energy transfer unit 210 is in the open state. By controlling the conduction sequence of the first switch G1 and the second switch G2 of the active energy transfer unit 210 and the third switch G3 of the passive energy consumption unit 310, the voltage between the battery clusters 100 is balanced, energy loss is avoided, and energy utilization is improved. By controlling the active flow and passive absorption of energy between the clusters, the voltage difference between the battery clusters 100 can be quickly brought to a reasonable range, suppressing the circulating current caused by the voltage imbalance between the battery clusters 100, while reducing costs, increasing battery life, and reducing the circulating current suppression time, thereby improving the efficiency and reliability of inter-cluster circulating current suppression.

[0081] In one embodiment, such as Figure 7 As shown, an inter-cluster circulation suppression method is provided, which can be applied to battery systems for ship energy storage and power supply. The inter-cluster circulation suppression method includes the following steps;

[0082] In step S710, when the maximum inter-cluster voltage difference in each battery cluster reaches the third preset threshold range, a second control signal is transmitted to the passive energy consumption circuit. The second control signal is used to instruct the passive energy consumption circuit to consume energy from the high-voltage battery clusters in each battery cluster so that the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range. The high-voltage battery clusters are the battery clusters in each battery cluster whose voltage is greater than the preset voltage threshold.

[0083] In step S720, when the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range, a first control signal is transmitted to the active energy transfer circuit. The first control signal is used to instruct the active energy transfer circuit to transfer energy to each battery cluster so that the maximum inter-cluster voltage difference in each battery cluster reaches the first preset threshold range. Any threshold of the third preset threshold range is greater than any threshold of the second preset threshold range. Any threshold of the second preset threshold range is greater than any threshold of the first preset threshold range.

[0084] For details regarding the inter-cluster circulation suppression method, please refer to the section on inter-cluster circulation suppression system above; it will not be repeated here.

[0085] Specifically, when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, i.e., when the inter-cluster voltage difference is too large, the processing unit transmits a second control signal to the energy passive consumption circuit. Based on the received second control signal, the energy passive consumption circuit consumes energy from the high-voltage battery clusters in each cluster. The energy passive consumption unit of the corresponding high-voltage battery cluster consumes the energy of the high-voltage battery cluster as heat, so that the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range. Then, the energy passive consumption circuit disconnects from operation. When the voltage difference between battery clusters is small within a preset threshold range, a first control signal is transmitted to the active energy transfer circuit. Based on the received first control signal, the active energy transfer circuit transfers energy to each battery cluster to bring the maximum inter-cluster voltage difference within each cluster to the first preset threshold range, thereby achieving voltage balance between battery clusters, preventing energy loss, and improving energy utilization. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between battery clusters can be quickly brought to a reasonable range, suppressing circulating currents caused by voltage imbalances between battery clusters, while reducing costs, increasing battery life, and shortening the circulating current suppression time.

[0086] In the above embodiments, the processing unit controls the active energy transfer circuit and the passive energy consumption circuit to achieve voltage balance between clusters. When the maximum inter-cluster voltage difference in each battery cluster falls within the second preset threshold range, the active energy transfer method between clusters is adopted, thereby avoiding energy loss and improving energy utilization. When the maximum inter-cluster voltage difference in each battery cluster falls within the third preset threshold range, the passive energy consumption method is adopted to reduce the number of battery charging cycles, improve battery life, and reduce energy transfer time, thereby improving the efficiency and reliability of inter-cluster circulating current suppression.

[0087] In one example, step S710, when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, includes the step of transmitting a second control signal to the energy passive consumption circuit:

[0088] When the maximum inter-cluster voltage difference in each battery cluster reaches the third preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each battery cluster. After the load pre-charging is completed, a second control signal is transmitted to the energy passive consumption circuit. The third control signal is used to instruct the pre-charge unit to pre-charge the load.

[0089] The processing unit can monitor the battery system's operating status in real time. After the battery system completes its self-test, it acquires the voltage of each battery cluster and compares the highest and lowest voltages among them. Based on the processing result, it obtains the maximum inter-cluster voltage difference. When the maximum inter-cluster voltage difference reaches a third preset threshold range (i.e., when the inter-cluster voltage difference is too large), the processing unit transmits a third control signal to the pre-charge unit of the highest-voltage battery cluster. This causes the highest-voltage battery cluster to activate its pre-charge branch, pre-charging the load side connected to the DC bus. Once the load pre-charging is complete, the pre-charge branch is disconnected, and a second control signal is transmitted to the energy passive consumption circuit. Based on the received second control signal, the energy passive consumption circuit consumes energy from the high-voltage battery clusters. The energy passive consumption unit of the corresponding high-voltage battery cluster dissipates the energy of the high-voltage battery cluster as heat, causing the maximum inter-cluster voltage difference to reach the second preset threshold range. At this point, the energy passive consumption circuit disconnects.

[0090] In one example, step S720, when the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range, includes the step of transmitting a first control signal to the active energy transfer circuit:

[0091] When the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each battery cluster. After the load pre-charging is completed, a first control signal is transmitted to the active energy transfer circuit. The third control signal is used to instruct the pre-charge unit to pre-charge the load.

[0092] When the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range, i.e., when the inter-cluster voltage difference is not large, the processing unit transmits a third control signal to the pre-charge unit of the highest voltage battery cluster in each cluster. This causes the highest voltage battery cluster to conduct the pre-charge branch of the pre-charge unit to pre-charge the load side connected to the DC bus. Once the load pre-charging is complete, the pre-charge branch of the pre-charge unit is disconnected, and a first control signal is transmitted to the active energy transfer circuit. The active energy transfer circuit transfers energy to each battery cluster according to the received first control signal, so that the maximum inter-cluster voltage difference in each battery cluster reaches the first preset threshold range, achieving voltage balance between battery clusters, avoiding energy loss, and improving energy utilization. By controlling the active flow and passive absorption of energy between clusters, the voltage difference between battery clusters can be quickly brought to a reasonable range, suppressing circulating currents caused by voltage imbalances between battery clusters, while reducing costs, increasing battery life, and reducing circulating current suppression time.

[0093] In one example, the inter-cluster circulation suppression method also includes the following steps:

[0094] When the maximum inter-cluster voltage difference in each battery cluster reaches the fourth preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each corresponding battery cluster. After the load pre-charging is completed, the third control signal is transmitted to the pre-charge unit of the remaining battery clusters in each corresponding battery cluster in sequence.

[0095] The processing unit acquires the voltage of each battery cluster and compares the highest and lowest voltages among them. Based on the processing result, it obtains the maximum inter-cluster voltage difference. When the maximum inter-cluster voltage difference reaches a fourth preset threshold range (i.e., when the inter-cluster voltage difference is small), the processing unit transmits a third control signal to the pre-charge unit of the highest-voltage battery cluster. This causes the highest-voltage battery cluster to preferentially close the pre-charge branch of the pre-charge unit, thus pre-charging the load side connected to the DC bus. Once the load pre-charging is complete, the main circuit of the pre-charge unit is closed, and the battery cluster is then powered on. Furthermore, a third control signal is transmitted sequentially to the pre-charge unit of the remaining battery clusters in each corresponding battery cluster, so that the remaining battery clusters are pre-charged in sequence, the main circuit of the corresponding pre-charge unit is closed, and the power-on process of the entire battery system is completed. Then, when the voltage difference between battery clusters is small, the pre-charge circuit is directly controlled to work, without the need to start the active energy transfer circuit for energy transfer or the passive energy consumption circuit for energy consumption. This can improve energy utilization, battery life, and improve the efficiency and reliability of inter-cluster circulating current suppression.

[0096] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the division operations described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0097] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An inter-cluster circulation suppression system, characterized in that, include: At least two battery clusters, each of which is used to supply power to the load via a DC bus; An active energy transfer circuit, comprising at least two active energy transfer units, each of which is matched and connected to each of the battery clusters in a one-to-one correspondence. The active energy transfer circuit is configured to transfer energy to each of the battery clusters according to the received first control signal, so that the maximum inter-cluster voltage difference in each of the battery clusters reaches a first preset threshold range. A passive energy consumption circuit, comprising at least two passive energy consumption units, each of which is matched and connected to each of the battery clusters in a one-to-one correspondence. The passive energy consumption circuit is configured to consume energy from the high-voltage battery clusters in each battery cluster according to the received second control signal, so that the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range; any threshold of the second preset threshold range is greater than any threshold of the first preset threshold range; the high-voltage battery cluster is the battery cluster in each battery cluster whose voltage is greater than a preset voltage threshold. The processing unit is configured to transmit the second control signal to the passive energy consumption circuit when the maximum inter-cluster voltage difference in each of the battery clusters reaches a third preset threshold range, and to transmit the first control signal to the active energy transfer circuit when the maximum inter-cluster voltage difference in each of the battery clusters reaches a second preset threshold range; any threshold of the third preset threshold range is greater than any threshold of the second preset threshold range. It also includes a pre-charging circuit; the pre-charging circuit includes at least two pre-charging units, each of which is matched and connected to each of the battery clusters; the pre-charging unit is configured to pre-charge the load according to a received third control signal; The processing unit is further configured to transmit the third control signal to the pre-charging unit corresponding to the highest voltage battery cluster in each battery cluster when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, until the load pre-charging is completed, and then transmit the second control signal to the passive energy consumption circuit; and to transmit the third control signal to the pre-charging unit corresponding to the highest voltage battery cluster in each battery cluster when the maximum inter-cluster voltage difference in each battery cluster reaches a second preset threshold range, until the load pre-charging is completed, and then transmit the first control signal to the active energy transfer circuit.

2. The inter-cluster circulation suppression system according to claim 1, characterized in that, The processing unit is further configured to transmit the third control signal to the pre-charging unit of the highest voltage battery cluster in each battery cluster when the maximum inter-cluster voltage difference in each battery cluster reaches a fourth preset threshold range, until the load pre-charging is completed, and then transmit the third control signal to the pre-charging unit of the remaining battery clusters in each battery cluster in sequence; the maximum threshold of the fourth preset threshold range is greater than the maximum threshold of the first preset threshold range.

3. The inter-cluster circulation suppression system according to any one of claims 1 to 2, characterized in that, The processing unit includes a processing chip, an MBMU domain management unit, a voltage acquisition unit, and at least two SBMU cluster management units; each SBMU cluster management unit is matched and connected to each battery cluster in a one-to-one correspondence; the voltage acquisition unit is configured to acquire the voltage of each battery cluster; The MBMU domain management unit is connected to the voltage acquisition unit and each of the SBMU cluster management units; the processing chip is connected to the MBMU domain management unit, the voltage acquisition unit, the active energy transfer circuit, and the passive energy consumption circuit.

4. The inter-cluster circulation suppression system according to claim 3, characterized in that, The active energy transfer unit includes a first switching transistor, a second switching transistor, a first capacitor, a first resistor, and a first fuse; The collector of the first switch is connected to the positive terminal of the corresponding battery cluster, the emitter of the first switch is connected to the collector of the second switch, the emitter of the second switch is connected to the DC bus, and the gates of the first switch and the second switch are respectively connected to the processing chip. The positive terminal of the first capacitor is connected to the emitter of the first switching transistor, the negative terminal of the first capacitor is connected to the first end of the first resistor, the second end of the first resistor is connected to the first end of the first fuse, and the second end of the first fuse is connected to the negative terminal of the corresponding battery cluster and the load, respectively.

5. The inter-cluster circulation suppression system according to claim 3, characterized in that, The passive energy consumption unit includes a third switch, a first diode, a second diode, a third diode, a second capacitor, a second resistor, a first inductor, and a second fuse; The anode of the first diode is connected to the emitter of the third switch, the positive terminal of the second capacitor, and the first terminal of the inductor. The cathode of the first diode is connected to the negative terminal of the corresponding battery cluster, the cathode of the second diode, the first terminal of the second resistor, and the first terminal of the second fuse. The collector of the third switch is connected to the anode of the second diode and the second terminal of the second resistor. The gate of the third switch is connected to the processing chip. The second terminal of the second fuse is connected to the negative terminal of the second capacitor and the cathode of the third diode. The anode of the third diode is connected to the positive terminal of the second capacitor and the first terminal of the first inductor. The second terminal of the first inductor is connected to the corresponding pre-charge unit.

6. The inter-cluster circulation suppression system according to claim 5, characterized in that, The pre-charge unit includes a third resistor, a main relay, and a pre-charge relay; The first end of the third resistor is connected to the first end of the precharge relay, the second end of the third resistor is connected to the first end of the main relay, and the second end of the precharge relay is connected to the second end of the main relay. The second end of the main relay is connected to the positive terminal of the corresponding battery cluster and the corresponding active energy transfer unit, respectively, and the first end of the main relay is connected to the first inductor.

7. The inter-cluster circulation suppression system according to claim 3, characterized in that, The processing unit also includes an energy distribution unit connected to the MBMU domain management unit.

8. A method for suppressing inter-cluster circulation, characterized in that, Includes the following steps: When the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range, a second control signal is transmitted to the passive energy consumption circuit. The second control signal is used to instruct the passive energy consumption circuit to consume energy from the high-voltage battery clusters in each battery cluster, so that the maximum inter-cluster voltage difference in each battery cluster reaches the second preset threshold range. The high-voltage battery clusters are battery clusters in each battery cluster whose voltage is greater than the preset voltage threshold. When the maximum inter-cluster voltage difference in each of the battery clusters reaches the second preset threshold range, a first control signal is transmitted to the active energy transfer circuit. The first control signal is used to instruct the active energy transfer circuit to transfer energy to each of the battery clusters so that the maximum inter-cluster voltage difference in each of the battery clusters reaches a first preset threshold range; any threshold of the third preset threshold range is greater than any threshold of the second preset threshold range; any threshold of the second preset threshold range is greater than any threshold of the first preset threshold range. The step of transmitting a second control signal to the energy passive consumption circuit when the maximum inter-cluster voltage difference in each battery cluster reaches a third preset threshold range includes: When the maximum inter-cluster voltage difference in each of the battery clusters reaches a third preset threshold range, a third control signal is transmitted to the pre-charge unit corresponding to the highest voltage battery cluster in each of the battery clusters. After the load pre-charging is completed, the second control signal is transmitted to the energy passive consumption circuit. The third control signal is used to instruct the pre-charge unit to pre-charge the load. The step of transmitting a first control signal to the active energy transfer circuit when the maximum inter-cluster voltage difference in each of the battery clusters reaches a second preset threshold range includes: When the maximum inter-cluster voltage difference in each of the battery clusters reaches the second preset threshold range, the third control signal is transmitted to the pre-charge unit corresponding to the highest voltage battery cluster in each of the battery clusters, until the load pre-charging is completed, and then the first control signal is transmitted to the energy active transfer circuit; the third control signal is used to instruct the pre-charge unit to pre-charge the load.

9. The inter-cluster circulation suppression method according to claim 8, characterized in that, It also includes the following steps: When the maximum inter-cluster voltage difference in each of the battery clusters reaches a fourth preset threshold range, a third control signal is transmitted to the pre-charge unit of the highest voltage battery cluster in each of the battery clusters. After the load pre-charging is completed, the third control signal is transmitted sequentially to the pre-charge units of the remaining battery clusters in each of the battery clusters.

Images