A new energy unmanned ship battery power control method and system

Abstract

The application discloses a new energy unmanned ship battery power control method and system, which comprises the following steps: an unmanned ship total system sends a start-stop instruction to a BMS to automatically wake up and start a battery pack; after the BMS is started, the voltage of a battery module, the main loop current and the temperature of key components are detected, and if normal, a pre-charging circuit is started to pre-charge a high-voltage loop capacitor; after pre-charging is completed, the BMS disconnects an auxiliary contactor, closes a main contactor, and the battery module supplies power to a power-consuming device; during operation, the BMS collects operation data in real time, and uploads the operation data to the unmanned ship total system for monitoring through an external CAN bus; when multiple battery packs are connected in parallel, the BMS controls the charging and discharging of the battery packs through the external CAN bus; the unmanned ship total system sends a shutdown instruction, and the BMS cuts off the main contactor; and when an abnormality is monitored, the BMS triggers a main fuse to be blown and cuts off the power supply of the BMS. The application solves the problem of safe starting, improves the precision of battery state monitoring, builds a multi-dimensional safety protection system and optimizes the collaborative control of multiple battery packs.

Description

Technical Field

[0001] This invention relates to the field of new energy ship power technology, specifically to a new energy unmanned surface vessel battery power control method and system. Background Technology

[0002] With the increasing demands in fields such as marine development, environmental monitoring, and security patrols, new energy unmanned surface vessels (USVs) have become an important development direction for maritime equipment due to their advantages such as zero emissions, low noise, and high stealth. Their power systems, as core components, must meet stringent requirements such as long endurance, high reliability, unmanned autonomous control, and adaptability to complex environments. However, traditional battery-powered systems face the following key technological challenges in application:

[0003] I. Challenges in Safe Start-up and High-Voltage Circuit Control

[0004] Unmanned surface vessels (USVs) rely on battery packs for independent power, and the high-voltage circuit capacitors are de-energized before startup. If the main contactor is closed directly, the high voltage of the battery module will instantly impact the capacitors, generating surge currents of hundreds to thousands of amperes, potentially causing contactor contacts to weld, capacitors to break down, or battery damage due to overcurrent. Traditional pre-charging schemes lack precise voltage synchronization judgment and overcurrent protection mechanisms, making them prone to startup failures due to insufficient pre-charging or circuit abnormalities, thus affecting mission safety.

[0005] II. Bottlenecks in Battery Status Monitoring and Health Management

[0006] Insufficient accuracy in SOC (State of Charge) estimation: Traditional current integration method is susceptible to noise interference and temperature drift, resulting in an error of more than 10% in remaining power, which may lead to misjudgment of battery life or task interruption.

[0007] SOH (State of Health) assessment is lagging: Existing methods mostly rely on static cycle count statistics, ignoring the impact of dynamic factors such as temperature and depth of discharge on capacity decay, and cannot reflect the degree of battery aging in real time.

[0008] III. Lack of a multi-dimensional security protection system

[0009] Temperature monitoring blind spot: Traditional systems only monitor the temperature of the battery cells and ignore the temperature changes of key components such as the main contactor and high-voltage capacitors, which can easily lead to circuit failure due to local overheating.

[0010] The hierarchical protection logic is imperfect: it lacks a tiered response mechanism for abnormal operating conditions such as overcurrent, high temperature, and low temperature, which often directly triggers emergency shutdown and affects the emergency return capability of the unmanned surface vessel.

[0011] IV. Challenges of Parallel and Coordinated Control of Multiple Battery Packs

[0012] To meet high power requirements, unmanned surface vessels (USVs) often adopt a multi-battery pack parallel architecture, but this has the following problems:

[0013] Current distribution imbalance: Inconsistencies in battery pack consistency cause some batteries to bear excessive current, accelerating the aging process;

[0014] Communication delay and interference: In complex electromagnetic environments, distributed control is prone to data packet loss, which can cause asynchronous charging and discharging commands, resulting in circulating current or power fluctuations. Summary of the Invention

[0015] In order to overcome the shortcomings of the prior art, the present invention aims to provide a new energy unmanned surface vessel battery power control method and system to solve the problem of safe start-up of high voltage circuit, improve the accuracy of battery status monitoring, build a multi-dimensional safety protection system, and optimize the collaborative control of multiple battery packs.

[0016] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0017] A method for controlling the battery power of a new energy unmanned surface vessel includes the following steps:

[0018] The unmanned surface vessel's overall system sends start / stop commands to the BMS via the external CAN bus, and the BMS connects to the external power supply to automatically wake up and start the battery pack.

[0019] After the BMS starts, it detects the battery module voltage, main circuit current and temperature of key components through current and temperature sensors. If the conditions are normal, the pre-charging circuit is started, and the high-voltage circuit capacitor is pre-charged through the pre-charging resistor.

[0020] After precharging is complete, the BMS disconnects the auxiliary contactor and closes the main contactor, and the battery module supplies power to the electrical equipment.

[0021] During operation, the BMS collects cell parameters, charging and discharging current, SOC and temperature data in real time, and uploads them to the unmanned surface vessel's overall system for monitoring via the external CAN bus; when multiple battery packs are connected in parallel, coordinated charging and discharging control is carried out through the external CAN bus using a master-slave communication protocol architecture.

[0022] The unmanned surface vessel's overall system sends a shutdown command according to a preset route or SOC threshold, and the BMS disconnects the main contactor; when overcurrent, high temperature or battery module abnormality is detected, the BMS triggers the main fuse to blow and cuts off its own power supply.

[0023] The real-time acquisition of cell parameters includes: real-time acquisition of individual cell voltage and total battery module voltage through BMS, and calculation of SOH through cycle count accumulation and capacity decay model.

[0024] Preferably, during pre-charging and closing of the main contactor, the following is included:

[0025] The high-voltage circuit capacitor voltage is monitored in real time by the control logic circuit. When the voltage reaches 90%~98% of the total voltage of the battery module, the pre-charge is determined to be completed. Then the auxiliary contactor is disconnected and the main contactor is closed after an interval of 100ms~300ms.

[0026] During pre-charging, the pre-charging circuit current is collected synchronously. When the peak value exceeds 1.2 times the rated current of the pre-charging resistor, the auxiliary contactor is immediately disconnected and overcurrent protection is triggered, and a fault code is uploaded through the external CAN bus.

[0027] Preferably, when calculating SOH using the cumulative cycle count and capacity decay model, the following is included:

[0028] The number of charge-discharge cycles of the battery module is recorded in real time by the BMS. The number of charge-discharge cycles = the number of full cycles + the number of equivalent full cycles. A full cycle is defined as a single charge-discharge process with a discharge depth ≥ 80%. The number of equivalent full cycles is determined based on the number of partial cycles with a discharge depth < 80% and its discharge depth.

[0029] Based on a capacity decay model that combines charge-discharge cycle count, basic decay coefficient, temperature-accelerated decay coefficient, and temperature range, the capacity of the battery module after decay is generated.

[0030] Based on the battery module's degraded capacity and rated capacity, the SOH is obtained.

[0031] Preferably, when acquiring SOC in real time, it includes:

[0032] The initial SOC value is obtained, and the charging and discharging current data collected by the current sensor is processed by a second-order low-pass filtering algorithm to calculate the average current value per unit time.

[0033] The SOC value to be compensated is calculated using the current integration method based on the average current value.

[0034] Temperature-dependent self-discharge compensation is performed on the SOC value to be compensated to obtain the SOC value.

[0035] Preferably, when obtaining the initial SOC value, the following steps are included:

[0036] During startup, the SOC value stored in the BMS non-volatile memory before the last power failure is read first as the initial SOC value; if there is no valid data, the total voltage of the battery module is measured by the open circuit voltage method, and the initial SOC value is obtained by querying the preset OCV-SOC mapping table.

[0037] When calculating the SOC value to be compensated, the following is included:

[0038] Using 0.1s to 1s as the integration time interval Δt, the average current value after second-order low-pass filtering is integrated based on the current actual capacity of the battery module to obtain the SOC value to be compensated.

[0039] When performing temperature-dependent self-discharge compensation, the following is included:

[0040] The compensation current is determined by querying the self-discharge coefficient table pre-installed in the BMS based on the real-time temperature collected by the temperature sensor, and the SOC value to be compensated is compensated based on the compensation current and the time interval Δt.

[0041] Preferably, when acquiring temperature data in real time via BMS, the following are included:

[0042] The temperature data was acquired using at least three NTC thermistors, and the following were monitored:

[0043] The cell temperature of the battery module, with sampling points covering the upper, middle and lower layers of cells within the battery module;

[0044] Contact temperature of the main contactor in the high-voltage control module;

[0045] Surface temperature of the capacitor in the high-voltage circuit;

[0046] The temperature sampling frequency is no less than 10Hz and is compared with a preset threshold in real time. If the threshold is exceeded, a graded protection logic is triggered.

[0047] Preferably, when the hierarchical protection logic is triggered, it includes:

[0048] When the temperature reaches 55℃ or -10℃, the BMS will send an early warning via the external CAN bus, and the unmanned surface vessel's overall system will adjust the power output to 80% and start heat dissipation or preheating.

[0049] When the temperature rises to 65℃ or drops to -20℃, the BMS limits the charging and discharging current to 50% of the rated value and sends a power limiting command via the external CAN bus, and the unmanned surface vessel's overall system switches to low-power cruise.

[0050] When the temperature exceeds 70℃ or falls below -25℃, or when the temperature changes by more than 5℃ / s within 10 seconds, the BMS disconnects the main contactor and transmits an emergency stop signal via the external CAN bus.

[0051] If the temperature does not drop after an emergency shutdown and remains above 70°C or below -25°C for 3 seconds, the BMS will trigger the main fuse to blow and isolate the high-voltage circuit.

[0052] Preferably, when performing coordinated charge and discharge control, it includes:

[0053] Designate one battery pack as the master controller and the rest as slave controllers;

[0054] The main controller periodically broadcasts a synchronization clock and charging / discharging command frames via an external CAN bus. The frame structure includes the total system current requirement, voltage limit threshold, preset maximum safe operating temperature threshold, and priority identifier.

[0055] After receiving instructions from the controller, the master controller feeds back its own status and dynamic parameters via the external CAN bus, and dynamically allocates the charging and discharging current of each slave controller accordingly.

[0056] Preferably, when dynamically allocating the charging and discharging current of each slave controller, the following is included:

[0057] The controller feeds back SOC, SOH, maximum allowable current of the battery pack, standard deviation of battery pack voltage, and temperature safety margin through the external CAN bus.

[0058] Kalman filtering algorithm is used to filter noise from SOC and SOH data and remove outliers;

[0059] The comprehensive weight of each slave controller is generated based on SOC, SOH, battery pack voltage standard deviation and temperature safety margin, combined with dynamic adjustment coefficients.

[0060] The basic allocation coefficients for each slave controller are generated based on the comprehensive weights;

[0061] Based on the dynamic allocation coefficient of the basic allocation, the total current demand of the system, and the maximum allowable current of the battery pack, the charging and discharging current of each slave controller is allocated.

[0062] When a controller approaches its current limit for several consecutive cycles, a load transfer mechanism is automatically triggered, allocating a portion of the current to other healthy battery packs.

[0063] A new energy unmanned surface vessel battery power control system, during operation, executes the above-mentioned method, including:

[0064] The battery pack has a built-in BMS that integrates current and temperature sensors. The BMS is electrically connected to the battery module. The current sensor monitors the main circuit current in real time for overcurrent protection, SOC calculation, and energy management. The temperature sensor monitors the temperature of key components and triggers heat dissipation.

[0065] The high-voltage control module, integrated within the battery pack, includes a main contactor, a pre-charging circuit, and a main fuse. The main contactor is electrically connected to the BMS and is responsible for controlling the on / off state of the main circuit. The main fuse is connected in series with the main circuit and melts in case of a short circuit or severe overcurrent to isolate the fault. The pre-charging circuit is electrically connected to the BMS and pre-charges the high-voltage circuit capacitor through a current-limiting resistor when the system starts up.

[0066] The communication module includes an external CAN bus interface. The BMS communicates with the unmanned surface vessel (USV) system through the external CAN bus interface to upload the battery pack's cell parameters, status data, and alarm information, and to receive power start / stop commands from the USV system.

[0067] The enclosure structure provides physical protection, isolating high-voltage and low-voltage areas;

[0068] The external CAN bus interface is configured to use a master-slave communication protocol architecture for coordinated charging and discharging control when multiple battery packs are connected in parallel.

[0069] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0070] (1) Improve system startup security and reliability

[0071] Precise pre-charge control: By real-time monitoring of the high-voltage circuit capacitor voltage and pre-charge current, combined with the timing control of the auxiliary contactor and the main contactor, the inrush current can be controlled to be less than 1.5 times the rated operating current, avoiding damage to contactors, capacitors and other components caused by the surge current caused by traditional direct closing.

[0072] Comprehensive self-inspection mechanism: Before startup, current sensors and temperature sensors are used to detect the battery module voltage, main circuit current and temperature of key components to ensure that startup is prohibited under abnormal conditions, thereby reducing the risk of failure from the source.

[0073] (2) Achieve accurate battery status perception and full life cycle management

[0074] High-precision SOC estimation: The algorithm of "second-order low-pass filtering + current integration + temperature-dependent self-discharge compensation" is adopted. The initial SOC value is read first from non-volatile stored data (and the OCV method is used for fallback when there is no valid data). The integration time interval is dynamically optimized (0.1s~1s) to effectively control the SOC error and solve the problem of noise and temperature drift affecting the traditional coulomb counting method.

[0075] Refined SOH Assessment: By accumulating the number of charge-discharge cycles (considering the partial cycle conversion of discharge depth <80%) through "full cycle + equivalent full cycle", and combining temperature range division and temperature-accelerated decay coefficient, a multi-factor coupled capacity decay model is constructed, which effectively improves the accuracy of SOH assessment and provides data support for battery replacement and maintenance.

[0076] (3) Construct a multi-dimensional security protection system

[0077] Full-range temperature monitoring and graded protection: By covering the temperature of the battery cell (upper, middle and lower layers), main contactor contacts and high-voltage capacitors with at least 3 NTC thermistors, combined with three-level protection logic and the main fuse blowing mechanism, the risk of thermal runaway can be prevented in all aspects.

[0078] Active and passive safety coordination: Normal shutdown achieves soft shutdown by cutting off the main contactor; under abnormal operating conditions, the main fuse is triggered to blow and cut off the BMS power supply, forming a closed-loop protection of "monitoring-early warning-isolation", which significantly improves the response speed compared with the traditional single protection mechanism.

[0079] (4) Optimize the efficiency and consistency of multi-battery pack parallel systems

[0080] Master-slave collaborative control architecture: Real-time interaction between the master controller and slave controller is achieved through an external CAN bus. The master controller periodically broadcasts a synchronization clock and command frames, while the slave controller feeds back parameters such as SOC, SOH, and voltage standard deviation, thus solving the problems of communication delay and data packet loss in distributed control.

[0081] Dynamic current allocation algorithm: Based on SOC, SOH, temperature safety margin, and voltage standard deviation, a comprehensive weight is generated. Combined with Kalman filtering to eliminate abnormal data, precise current allocation is achieved through a basic allocation coefficient and the maximum allowable current limit. When a battery pack approaches its current limit for three consecutive cycles, 10%~15% of the current is automatically transferred to the healthy battery pack to avoid accelerated local aging caused by current imbalance and extend the system cycle life.

[0082] (5) Convenience of intelligent energy management and operation and maintenance

[0083] Full lifecycle data interaction: Real-time uploading of cell parameters, SOC, SOH, temperature and other data via external CAN bus, supporting remote monitoring and fault diagnosis of the unmanned surface vessel system (such as uploading precharge overcurrent fault codes), enabling battery status assessment and maintenance decisions without manual intervention.

[0084] Adaptive operating condition adjustment: Based on SOC thresholds (such as automatic switching to low-power cruise when the battery is low) and shutdown control of preset routes, combined with temperature-dependent charging and discharging strategies (low-temperature preheating, high-temperature heat dissipation), energy utilization efficiency can be dynamically optimized to improve the endurance of unmanned surface vessels.

[0085] (6) Structural integration and environmental adaptability improvement

[0086] High-voltage and low-voltage area isolation: The high-voltage control module (main contactor, pre-charging circuit, main fuse) is physically isolated from the low-voltage BMS through the enclosure structure. With the high-voltage connector with an IP67 or higher protection rating, it meets the usage requirements of complex marine environments (salt spray, vibration, shock).

[0087] Modular design: The battery pack has a built-in BMS and communication module, supports parallel expansion of multiple packs, and can flexibly configure the capacity according to the power requirements of the unmanned surface vessel, reducing the difficulty of system integration and maintenance costs.

[0088] In summary, this invention effectively addresses the key technical challenges in safety, reliability, efficiency, and adaptability of new energy unmanned surface vessel (USV) battery power systems through a comprehensive control strategy encompassing "safe start-up, precise monitoring, intelligent collaboration, and tiered protection," providing core technical support for the long-endurance and highly reliable operation of USVs.

[0089] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0090] Figure 1 This is a flowchart illustrating the battery power control method for new energy unmanned surface vessels according to an embodiment of the present invention.

[0091] Figure 2 This is a circuit diagram of the new energy unmanned surface vessel battery power control system according to an embodiment of the present invention;

[0092] Figure 3 This is an interaction diagram of the battery pack and the unmanned surface vessel system according to an embodiment of the present invention.

[0093] Explanation of reference numerals: 20. Unmanned surface vessel main system; 21. Battery pack; 211. Battery management system; 212. Battery module; 213. Main contactor; 214. Main fuse; 215. External CAN bus interface; 216. Internal CAN bus interface; 217. BMS power supply interface; 218. Main busbar; 219. Precharge resistor; 220. Auxiliary contactor; 221. High voltage connector; 222. Busbar; 223. Positive battery module; 224. Negative battery module; 225. Auxiliary fuse. Detailed Implementation

[0094] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0095] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0096] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0097] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0098] Example 1, see Figure 1 The present invention provides a step-by-step diagram of a new energy unmanned surface vessel battery power control method, as shown in the diagram. Figure 1 The method for controlling the battery power of a new energy unmanned surface vessel, as shown, includes the following steps:

[0099] S101. Remote start-stop control: The unmanned surface vessel system 20 sends a power start-stop command to the battery management system 211 (BMS) built into the battery pack 21 via the external CAN bus. After receiving the command, the BMS connects to the external power supply through its power supply interface to realize the automatic wake-up and start-up of the battery pack 21 without manual operation.

[0100] S102. System self-test and pre-charge control: After the BMS starts, it detects the voltage of the battery module 212, the main circuit current and the temperature of key components in the box through the integrated current sensor and temperature sensor. If the detection results are normal, it controls the pre-charge circuit to start and pre-charges the high-voltage circuit capacitor through the pre-charge resistor 219 in the pre-charge circuit.

[0101] S103. High-voltage circuit on / off control: After pre-charging is completed, the auxiliary contactor 220 is disconnected through the BMS and the main contactor 213 is closed, so that the battery module 212 supplies power to the unmanned surface vessel's electrical equipment through the main busbar 218;

[0102] S104. Real-time monitoring and data interaction: During operation, the BMS collects cell parameters, charging and discharging current, SOC (state of charge) and temperature data in real time, and uploads them to the unmanned surface vessel's main system 20 via the external CAN bus. The data is then centrally displayed on the main system monitor or remotely monitored in the background. When multiple battery packs 21 are connected in parallel, the external CAN bus is used to perform coordinated charging and discharging control between battery packs 21 using a master-slave communication protocol architecture.

[0103] S105. Automatic shutdown and safety protection: The unmanned surface vessel system 20 sends a shutdown command according to the preset cruise route or battery SOC threshold. After receiving the command, the BMS disconnects the main contactor 213 and disconnects the high-voltage circuit. If continuous overcurrent, high temperature or abnormal battery module 212 is detected, the BMS automatically triggers the main fuse 214 to blow and cuts off the BMS power supply to achieve passive safety protection.

[0104] Background Description: In the battery power system of new energy unmanned surface vessels (USVs), the voltage, main circuit current, and temperature of key components of battery module 212 are core parameters for ensuring safe startup and stable operation of the system. Because USVs operate in complex aquatic environments and rely on battery pack 21 for independent power, any abnormalities in the battery system, such as overcurrent, overvoltage, undervoltage, or extreme temperature, could lead to serious accidents such as power interruption, equipment damage, or even battery thermal runaway. Therefore:

[0105] In step S102 above, detecting the voltage of battery module 212, main circuit current, and temperature of key components inside the box includes:

[0106] The charging and discharging current data of the main circuit is collected in real time by a current sensor. After processing by a filtering algorithm, the average current value per unit time is calculated for overcurrent protection judgment.

[0107] Real-time detection of the total voltage of the battery module and the voltage of individual cells is performed, with the detection accuracy error of the individual cell voltage not exceeding ±5mV and the detection accuracy error of the total voltage of the battery module not exceeding ±20mV.

[0108] The temperature sensors are used to monitor at least the cell temperature of the battery module 212, the temperature of the main contactor 213 in the high voltage control module, and the capacitor temperature of the high voltage circuit, with a sampling frequency of not less than 10Hz.

[0109] The detected current, voltage, and temperature data are compared with preset thresholds, including overcurrent protection threshold, upper and lower voltage limit threshold, high temperature alarm threshold (55℃~65℃), and low temperature protection threshold (-20℃~-10℃). If any parameter exceeds the threshold range, the BMS immediately generates a fault code and triggers the corresponding protection logic.

[0110] In this embodiment of the invention, it is necessary to further explain that the detection mechanism provided in this embodiment constructs a "safety defense line" before the battery system starts up through high-precision sensing, multi-parameter collaborative monitoring, and graded threshold protection:

[0111] Current monitoring: Real-time current data is processed using a filtering algorithm to eliminate high-frequency noise interference, ensure the accuracy of overcurrent protection judgment, and avoid false triggering of protection by instantaneous inrush current;

[0112] Voltage monitoring: Strictly control the detection accuracy of individual cells (±5mV) and total voltage (±20mV) to ensure accurate assessment of the health status of battery module 212 and prevent cell damage caused by voltage imbalance;

[0113] Temperature monitoring: Covering key components such as battery cells, main contactor 213 contacts and high-voltage capacitors, it captures dynamic temperature changes with high-frequency sampling of ≥10Hz, and combines a high temperature alarm threshold of 55℃~65℃ and a low temperature protection threshold of -20℃~-10℃ to achieve wide-range temperature anomaly early warning.

[0114] Threshold linkage: By comparing current, voltage, and temperature parameters with preset thresholds in real time, a multi-dimensional fault diagnosis logic is formed to ensure that any parameter exceeding the limit can immediately trigger a fault code and protection mechanism, providing a safe premise for subsequent pre-charge control and high-voltage circuit startup.

[0115] The aforementioned detection mechanism, through closed-loop control of "precise perception - real-time analysis - rapid response," lays the foundation for the safe startup and stable operation of the unmanned surface vessel's battery system.

[0116] Background Description: In the high-voltage power system of new energy unmanned surface vessels, the high-voltage circuit capacitor is usually de-energized before system startup. If the main contactor 213 is directly closed to directly connect the high voltage of the battery module 212 to the circuit, the instantaneous voltage difference across the capacitor will generate a surge current of hundreds or even thousands of amperes, which may cause the contacts of the main contactor 213 to weld, the capacitor to break down, or the battery module 212 to be damaged by instantaneous overcurrent, seriously affecting system safety and equipment lifespan. In addition, if overcurrent occurs during pre-charging due to problems such as circuit short circuit, improper selection of pre-charging resistor 219, or abnormal capacitor, the lack of real-time monitoring and protection mechanisms may lead to cascading failures such as circuit overheating and component burnout. Based on this:

[0117] In steps S102 and S103 above, the pre-charging and closing of the main contactor 213 include:

[0118] The high-voltage circuit capacitor voltage is monitored in real time by the control logic circuit. When the capacitor voltage reaches 90%~98% of the total voltage of the battery module, the pre-charging is determined to be completed. Then the auxiliary contactor 220 is disconnected, and the main contactor 213 is controlled to close after an interval of 100ms~300ms to ensure that the capacitor voltage and the battery module 212 voltage tend to be consistent, and to eliminate the closing impact caused by the potential difference.

[0119] During the pre-charging process, the control logic circuit synchronously collects the pre-charging circuit current through the current sensor. When the peak current exceeds 1.2 times the rated current of the pre-charging resistor 219, the auxiliary contactor 220 is immediately disconnected and the overcurrent protection is triggered. The fault code "pre-charging overcurrent" is uploaded through the external CAN bus.

[0120] In this embodiment of the invention, it needs to be further explained that the pre-charging resistor 219 (5Ω~20Ω) in the pre-charging circuit is connected to the high-voltage circuit, utilizing the current-limiting characteristic of the resistor. This limits the charging current to a safe range (usually 10% to 20% of the battery's rated current), allowing the capacitor voltage to gradually increase from 0V.

[0121] The control logic circuit monitors the high-voltage circuit capacitor voltage in real time. When the voltage reaches 90%~98% of the total battery module voltage, pre-charging is considered complete. At this time, the potential difference between the capacitor and battery module 212 is ( The inrush current when closing the main contactor 213 can be controlled to be less than 1.5 times the rated operating current, thus meeting the contactor's safe engagement conditions.

[0122] Coordinated operation of auxiliary contactor 220 and main contactor 213:

[0123] Pre-charge stage: Auxiliary contactor 220 closes, pre-charge resistor 219 is connected to the circuit, and capacitor is charged through current-limiting path.

[0124] Switching phase: After pre-charging is completed, first disconnect the auxiliary contactor 220 (cut off the pre-charging circuit), and after an interval of 100ms~300ms, close the main contactor 213 (connect to the main circuit).

[0125] The purpose of the interval is to avoid the "short circuit of pre-charge resistor 219" caused by the simultaneous conduction of auxiliary contactor 220 and main contactor 213 (if both circuits are connected at the same time, the pre-charge resistor 219 will be short-circuited by the main contactor 213, and a surge current will still be generated); at the same time, the short interval allows the capacitor voltage to stabilize after the auxiliary contactor 220 is disconnected due to the slight fluctuation of circuit parasitic parameters (such as line inductance), ensuring complete synchronization with the battery voltage.

[0126] Overcurrent protection mechanism:

[0127] Immediate cut-off: When an overcurrent occurs, the control logic circuit quickly disconnects the auxiliary contactor 220 to terminate the pre-charge process and prevent the pre-charge resistor 219 from burning out due to overcurrent and overheating or the battery module 212 from being over-discharged.

[0128] Fault reporting: The fault code "precharge overcurrent" is uploaded to the unmanned surface vessel's main system 20 via the external CAN bus, triggering an alarm in the main system and prohibiting subsequent startup processes until the fault is resolved.

[0129] The core principle of pre-charging and main contactor 213 control is to transform the dynamic commissioning process of the high-voltage circuit from "instantaneous impact" to "smooth transition" through current-limited pre-charging, voltage synchronization, timing isolation and real-time overcurrent protection. This not only protects key components such as contactors and capacitors, but also provides a reliable guarantee for the safe start-up of the unmanned surface vessel's power system.

[0130] Background Description: In the battery power system of new energy unmanned surface vessels (USVs), real-time monitoring of cell parameters and state of health (SOH) assessment are core aspects of ensuring safe battery operation, extending service life, and optimizing energy management. As independently operating amphibious equipment, USVs' battery systems are constantly in a dynamic charging and discharging state, and operate in complex environments (such as temperature fluctuations, vibration, and shock). Cell performance gradually degrades with increasing cycle count and accumulated environmental stress. Without accurately understanding the cell voltage, cycle life, and capacity degradation patterns, it is difficult to provide a reliable basis for USV range planning. Therefore:

[0131] In step S104 above, when collecting cell parameters in real time via BMS, the following is included:

[0132] The battery management system collects the voltage of individual cells and the total voltage of the battery module in real time, and calculates the state of health (SOH) of the cells by accumulating the number of cycles and using a capacity decay model.

[0133] Among them, the cell parameters include the voltage of a single cell, the total voltage of the battery module, and the state of health (SOH) of the cell. The detection accuracy error of the voltage of a single cell shall not exceed ±5mV, and the detection accuracy error of the total voltage of the battery module shall not exceed ±20mV.

[0134] In one possible embodiment, calculating the cell state of health (SOH) includes:

[0135] Accumulated cycle count: The BMS records the charge / discharge cycle count of battery module 212 in real time (charge / discharge cycle count = full cycle count + equivalent full cycle count), where a full cycle is defined as a single charge / discharge process with a discharge depth ≥ 80%. Partial cycles (discharge depth < 80%) are converted into equivalent full cycle counts using the following formula:

[0136] ;

[0137] In the formula, To achieve the equivalent number of full loops, For the first Depth of discharge in the second partial cycle (range 0~80%). This represents the total number of iterations for a portion of the loop;

[0138] Capacity degradation model: The capacity of battery module 212 after degradation is calculated using an empirical degradation formula based on the number of charge-discharge cycles. The formula is as follows:

[0139] ;

[0140] In the formula, This refers to the capacity of battery module 212 after degradation. For the rated capacity of battery module 212, The basic attenuation coefficient (range 0.0005~0.002) -1 ), This refers to the number of charge-discharge cycles. The temperature-accelerated decay coefficient (value range 0.001~0.003 / ℃·cycle). For the first The average operating temperature across the temperature range (Base temperature 25℃) This represents the number of cycles within the corresponding temperature range. This indicates that the battery operating temperature range is divided into... A series of continuous and non-overlapping temperature ranges, each corresponding to a characteristic temperature range (e.g., -20℃~0℃, 0℃~25℃, 25℃~40℃, etc.).

[0141] Based on the degraded capacity and rated capacity of battery module 212, the state of health (SOH) of the cell is obtained, as shown in the following formula:

[0142] .

[0143] In this embodiment of the invention, it is necessary to further explain that accurate assessment of SOH is achieved through high-precision voltage monitoring (±5mV for individual cells, ±20mV for total voltage), refined cycle count accumulation (distinguishing between full cycles and partial cycles), and a multi-factor coupled capacity decay model (introducing a temperature-accelerated decay coefficient and temperature range division). Its core objective is:

[0144] Improved state perception accuracy: Captures cell equilibrium state through high-precision voltage detection, providing reliable basic data for SOH calculation;

[0145] Quantitative Cycling and Environmental Impact: By using equivalent full-cycle conversion and temperature range decay coefficient, the battery aging process under complex operating conditions is transformed into a calculable mathematical model;

[0146] Ensuring the reliability of unmanned surface vessel (USV) missions: Based on accurate State of Health (SOH) data, the USV system 20 can dynamically adjust its cruise strategy (such as returning to base early or reducing load) to avoid mission failures or safety incidents caused by a sudden drop in battery performance.

[0147] In summary, the proposed method for real-time acquisition of battery cell parameters and SOH calculation addresses the health management needs of new energy unmanned surface vessel (USV) battery systems in complex environments. Through multi-dimensional parameter fusion and refined model design, it achieves accurate perception of battery status and full life-cycle management, providing key technical support for the safe and efficient operation of USVs.

[0148] Background Description: In the battery power system of new energy unmanned surface vessels (USVs), State of Charge (SOC), as a core parameter characterizing the remaining battery capacity, directly determines the USV's endurance, mission planning reliability, and energy management efficiency. However, USVs operate in complex aquatic environments (such as temperature fluctuations, strong electromagnetic interference, vibration, and shock) and rely on independent power from the battery pack 21. Traditional SOC estimation methods face the following key challenges: current measurement noise and integral drift, and the significant impact of temperature on self-discharge characteristics. Based on this:

[0149] In step S104 above, when collecting SOC (State of Charge) in real time via BMS, the following steps are included:

[0150] The initial SOC value is obtained, and the charging and discharging current data collected by the current sensor is processed by a second-order low-pass filtering algorithm to calculate the average current value per unit time.

[0151] The SOC value to be compensated is calculated based on the average current value using the current integration method (Coulomb counting method).

[0152] Temperature-dependent self-discharge compensation is performed on the SOC value to be compensated to obtain the SOC value.

[0153] In one possible embodiment, obtaining the initial SOC value includes:

[0154] When the system starts up, it first reads the SOC value stored in the non-volatile memory in the BMS before the last power failure as the initial SOC value.

[0155] If there is no valid data in the non-volatile memory (such as during the first boot or when data is lost), the total voltage of the battery module is measured by the open-circuit voltage method (OCV), and the initial SOC value is obtained by querying the preset OCV-SOC mapping table.

[0156] When calculating the SOC value to be compensated, the following is included:

[0157] Using 0.1s to 1s as the integration time interval Δt, the average current value after second-order low-pass filtering ( The integral is performed to obtain the SOC value to be compensated. The integral formula is:

[0158] ;

[0159] In the formula, The SOC value to be compensated. The current actual capacity of battery module 212 (obtained through SOH calculation, i.e.) ), for The average current value at any given time is taken as positive during discharge and negative during charging; This is the initial SOC value;

[0160] When performing temperature-dependent self-discharge compensation, the following is included:

[0161] The compensation current is determined by consulting the self-discharge coefficient table pre-installed in the BMS based on the real-time temperature (T) collected by the temperature sensor. The SOC value to be compensated is then compensated based on this compensation current. The compensation formula is as follows:

[0162] ;

[0163] In the formula, SOC value To compensate for the current, The time interval is 0.1s to 1s.

[0164] In this embodiment of the invention, it is necessary to further explain that the proposed method for SOC acquisition is a multi-stage collaborative optimization: the initial value dual-source acquisition mechanism of "non-volatile storage priority + OCV backup" ensures the reliability of the SOC benchmark during the startup phase; the current data quality is optimized by second-order low-pass filtering and dynamic integral interval, and combined with a temperature-dependent self-discharge compensation model, high-precision SOC estimation under all operating conditions is achieved, providing core technical support for the unmanned surface vessel's endurance planning, safety protection and energy-efficient utilization.

[0165] Background Description: In the battery power system of new energy unmanned surface vessels (USVs), temperature is a core factor affecting battery safety, reliability, and lifespan. USVs operate for extended periods in complex aquatic environments, facing multiple temperature challenges such as direct sunlight, fluctuating water temperatures, and intense heat dissipation from equipment. If the battery system lacks accurate monitoring and intelligent protection mechanisms, the following risks can easily arise: safety hazards, accelerated performance degradation, and reduced mission reliability. Based on this:

[0166] In step S104 above, when acquiring temperature data in real time via BMS, the following is included:

[0167] Temperature data is collected using at least three NTC thermistors, and monitored separately:

[0168] The cell temperature of battery module 212, with sampling points covering the upper, middle and lower layers of cells inside battery module 212;

[0169] The contact temperature of the main contactor 213 in the high-voltage control module;

[0170] Surface temperature of the capacitor in the high-voltage circuit;

[0171] The temperature sampling frequency is no less than 10Hz and is compared with the preset thresholds (high temperature alarm threshold 55℃~65℃, low temperature protection threshold -20℃~-10℃) in real time. If the threshold is exceeded, the hierarchical protection logic is triggered.

[0172] In one possible embodiment, triggering the hierarchical protection logic includes:

[0173] Level 1 warning: When the temperature reaches the lower limit of the high temperature alarm threshold (55℃) or the upper limit of the low temperature protection threshold (-10℃), the temperature warning information is uploaded through the BMS based on the external CAN bus, the power output power is adjusted to 80% of the rated value through the unmanned surface vessel system 20, and active heat dissipation (fan or liquid cooling system) or preheating program is started.

[0174] Level 2 power limiting: If the temperature continues to rise to the upper limit of the high temperature alarm threshold (65℃) or drop to the lower limit of the low temperature protection threshold (-20℃), the charging and discharging current is limited to 50% of the rated value through the BMS, and a power limiting command is sent through the external CAN bus. The unmanned surface vessel system 20 switches to low power cruise mode.

[0175] Level 3 Emergency Shutdown: When the temperature exceeds the high temperature protection threshold (65℃+5℃ buffer) or falls below the low temperature protection threshold (-20℃-5℃ buffer), or when the temperature rises / falls at a rate exceeding 5℃ / s within 10 seconds, the main contactor 213 is immediately disconnected via the BMS to stop the high voltage output, and an emergency shutdown signal is transmitted via the external CAN bus.

[0176] Passive fuse protection: If the temperature does not drop after a level 3 emergency shutdown and remains above 70°C (high temperature) or below -25°C (low temperature) for 3 seconds, the main fuse 214 will be triggered by the BMS to completely isolate the high-voltage circuit.

[0177] In this embodiment of the invention, it is necessary to further explain that the embodiment uses at least three NTC thermistors to monitor the temperature of the battery cell (upper, middle and lower layers), the main contactor 213 contact and the high voltage capacitor respectively, so as to realize the full-domain temperature sensing of "battery cell-component-circuit" and avoid local overheating blind spots.

[0178] The 10Hz sampling frequency ensures real-time capture of temperature changes (such as capacitor charging and discharging heat, contactor arcing high temperature), providing data support for rapid protection.

[0179] The high sensitivity of NTC thermistors (temperature coefficient -3% / ℃) allows for accurate identification of temperature changes of ±1℃, ensuring the accuracy of threshold judgment.

[0180] Level 1 warning (55℃ / -10℃): By reducing power (80% of rated value) and actively controlling temperature (heat dissipation / preheating), intervention is made in the early stage of abnormal temperature to avoid triggering emergency shutdown and affecting mission execution.

[0181] Level 2 power limiting (65℃ / -20℃): Further limits the current to 50% and switches to low power mode to prioritize the return capability of the unmanned surface vessel and reduce the battery load under extreme temperatures.

[0182] Level 3 Emergency Shutdown (70℃ / -25℃ or 5℃ / s sudden change): By cutting off the main contactor 213, the high-voltage circuit is quickly isolated to prevent thermal runaway from spreading and to buy time for the unmanned surface vessel to respond autonomously.

[0183] Passive fuse protection: As the last line of defense, the main fuse 214 can completely isolate the faulty battery pack 21, avoid the spread of fire or the risk of electric shock, and ensure the overall safety of the unmanned surface vessel.

[0184] Background Description: In the parallel power system of multiple battery packs 21 of new energy unmanned surface vessels, to meet the requirements of long endurance and high power, multiple battery packs 21 are usually connected in parallel to form an energy matrix. However, due to the differences in production consistency among the battery packs 21, the different aging rates during use (such as differences in SOC and SOH), uneven temperature distribution, and discrete charging and discharging characteristics, the following risks may easily arise if an effective coordinated control mechanism is lacking:

[0185] Current distribution imbalance: Some battery packs 21 have low internal resistance or high capacity and bear excessive current, resulting in overcharging and over-discharging, which accelerates aging.

[0186] Deterioration of state consistency: The differences in SOC, voltage and temperature among the battery packs 21 gradually widen, triggering the "barrel effect", and the overall system capacity is limited by the weakest battery pack 21.

[0187] Communication delays and interference: In the complex electromagnetic environment of unmanned surface vessels, traditional distributed control is prone to data transmission packet loss or delay, resulting in asynchronous charging and discharging commands, which can cause circulating current or power fluctuations.

[0188] Safety Hazard: If battery pack 21 experiences abnormalities such as overcurrent or high temperature, the lack of a rapid and coordinated protection mechanism may lead to the fault spreading and causing the entire system to fail. Based on this:

[0189] In step S104 above, when performing coordinated charging and discharging control among the battery packs 21, the following is included:

[0190] Designate one of the battery packs 21 as the master controller and the other battery packs 21 as slave controllers;

[0191] The main controller periodically broadcasts a synchronous clock signal and charging / discharging command frames via an external CAN bus. The frame structure includes the total system current requirement, voltage limit threshold, preset maximum safe operating temperature threshold, and priority identifier.

[0192] After receiving the charge / discharge command frame from the controller, the slave controller feeds back its own status and dynamic parameters through the external CAN bus. The master controller dynamically allocates the charge / discharge current to each slave controller based on the feedback data.

[0193] In one possible embodiment, when the master controller dynamically allocates the charging and discharging current of each slave controller based on feedback data, it includes:

[0194] The controller feeds back its own SOC (State of Charge), SOH (State of Health), and maximum allowable current of the battery pack via an external CAN bus;

[0195] The controller feeds back the current battery pack voltage standard deviation and temperature safety margin (the difference between the current voltage and the preset maximum safe operating temperature threshold) via the external CAN bus.

[0196] Kalman filtering algorithm is used to filter noise in SOC and SOH data and remove outliers (such as jump data caused by communication packet loss).

[0197] The comprehensive weights of each slave controller are generated based on SOC (State of Charge), SOH (State of Health), battery pack voltage standard deviation, and temperature safety margin, as shown in the following formula:

[0198] ;

[0199] In the formula, For the first The overall weight from the controller, , , , These are dynamic adjustment coefficients, and their sum is 1. To provide a safety margin for temperature, To preset the maximum safe operating temperature threshold, For the first The real-time temperature from the controller, For the first The standard deviation of the battery pack voltage from the controller (compared to the standard deviation of the voltage limit threshold). For the first The SOC value of the controller. For the first The SOH value from the controller;

[0200] The basic allocation coefficients for each slave controller are generated based on the comprehensive weights, as shown in the following formula:

[0201] ;

[0202] In the formula, For the first A base allocation coefficient from the controller, Total number of controllers;

[0203] Based on the dynamic allocation coefficient, total system current demand, and maximum allowable current of the battery pack, the charging and discharging current of each slave controller is allocated as follows:

[0204] ;

[0205] In the formula, For the first The charging and discharging current allocated by the controller, For the total current requirement of the system, For the first The maximum allowable current of the battery pack from the controller;

[0206] When a controller approaches its current limit for three consecutive cycles, the load transfer mechanism is automatically triggered, allocating 10% to 15% of the current to other healthy battery packs 21.

[0207] The state parameters include: SOC (State of Charge), SOH (State of Health), and the maximum allowable current of the battery pack; the dynamic parameters include: the standard deviation of the battery pack voltage and the temperature safety margin.

[0208] In this embodiment of the invention, it is necessary to further explain that this embodiment achieves real-time interaction and precise current allocation among multiple battery packs (21 states) through a master-slave communication architecture and a dynamic collaborative control strategy, thereby ensuring the efficient and safe operation of the system. The specific principle is as follows:

[0209] I. Master-Slave Communication Architecture Design

[0210] (1) Role division

[0211] Main controller: Designates a battery pack 21 as the master node, responsible for global command generation, data fusion and current distribution decision, and periodically broadcasts synchronization clock signals and charge / discharge command frames through the external CAN bus (e.g., every 10ms).

[0212] Slave Controller: The remaining battery packs 21 act as slave nodes, receiving instructions from the master controller, providing real-time feedback of their own status parameters, and executing the current instructions assigned by the master controller.

[0213] (2) Communication protocol and frame structure

[0214] External CAN bus: Adopts the high-reliability CAN 2.0B protocol, supports real-time communication between multiple nodes, with a communication rate of no less than 500kbps, and ensures that the command transmission delay is ≤10ms.

[0215] Command frame content includes: total system current requirement (calculated in real time by the unmanned surface vessel system 20 based on the load), voltage limit threshold (e.g., maximum voltage of a single battery cell is 4.2V, minimum voltage is 2.5V), preset maximum safe operating temperature threshold (e.g., 65℃), and priority indicator (prioritize power supply to the power system in emergency mode).

[0216] II. State Parameter Feedback Mechanism

[0217] Two types of key parameters are fed back from the controller to the main controller via the external CAN bus:

[0218] (1) State parameters (static characteristics)

[0219] SOC (State of Charge): Reflects the remaining electrical charge, calculated using coulomb counting combined with temperature compensation.

[0220] State of Health (SOH): Reflects the degree of battery aging and is estimated based on a cycle count and capacity decay model.

[0221] Maximum allowable current: The upper limit of charge and discharge current calculated based on the current SOC, SOH and temperature (if SOH < 80%, the maximum allowable current is reduced by 20%).

[0222] (2) Dynamic parameters (real-time characteristics)

[0223] Voltage standard deviation: reflects the voltage balance of cells within the battery pack 21. The smaller the standard deviation, the better the consistency.

[0224] Temperature safety margin: The difference between the current temperature and the preset maximum safe temperature threshold directly affects the charging and discharging capability.

[0225] III. Dynamic Current Distribution Algorithm

[0226] Based on feedback data from the slave controller, the main controller achieves precise current distribution through the following steps:

[0227] (1) Data preprocessing

[0228] Kalman filtering algorithm is used to filter noise in data such as SOC and SOH, and eliminate jump values ​​caused by communication packet loss or sensor anomalies (such as instantaneous fluctuations of SOC exceeding 5%).

[0229] (2) Calculation of comprehensive weight

[0230] Generate comprehensive weights from the controller based on multi-dimensional parameters. ,in: , , , For dynamic adjustment coefficients (summing up to 1, such as in high-temperature environments) (Weight increased to 0.4). This represents the standard deviation of the battery pack voltage; the smaller the value, the higher the weight (prioritizing battery packs with good voltage balance 21).

[0231] (3) Basic allocation factor and current limit

[0232] Calculate the basic allocation coefficient for each slave controller, and dynamically allocate the charging and discharging current by combining the total current demand of the system with the maximum allowable current.

[0233] Load transfer mechanism: If a slave controller approaches its current limit for three consecutive cycles (e.g., ... It automatically transfers 10% to 15% of its current share to other healthy battery packs 21 to avoid overcurrent risk.

[0234] This embodiment prioritizes battery packs 21 with good health and high consistency by using a weighted approach based on State of Health (SOH) and voltage standard deviation, avoiding overcharging and over-discharging of weaker battery packs 21 and reducing the overall aging rate. Battery packs 21 with low temperature safety margins automatically reduce current distribution, combined with graded protection logic (such as power reduction at 55℃ and emergency shutdown at 65℃) to prevent thermal runaway. The high real-time performance of the external CAN bus and the Kalman filtering algorithm ensure reliable data transmission even in environments with strong electromagnetic interference, with a current distribution response delay of <50ms. Through these principles, the multi-battery pack 21 system achieves closed-loop control of "state perception - dynamic decision-making - precise execution," significantly improving the endurance and power system reliability of the unmanned surface vessel.

[0235] Example 2, see Figure 2 Circuit diagram and Figure 3 The present invention provides an interactive diagram, such as... Figure 2 and Figure 3 The battery power control system of a new energy unmanned surface vessel shown includes: a battery pack 21, a high-voltage control module, a communication module, and a housing structure.

[0236] The battery pack 21 has a built-in battery management system 211 (BMS), which integrates current sensors and temperature sensors and is electrically connected to the battery module 212. The current sensors (such as Hall sensors and shunts) monitor the main circuit current in real time and provide charging and discharging current data for overcurrent protection, SOC (state of charge) calculation and energy management. The temperature sensors are used to monitor the temperature of key components inside the pack and trigger the fan or liquid cooling system for heat dissipation.

[0237] The high-voltage control module is integrated into the battery pack 21 and includes a main contactor 213, a pre-charging circuit, and a main fuse 214. The main contactor 213 and the pre-charging circuit are electrically connected to the BMS. The main contactor 213 is responsible for the on / off control of the main circuit and quickly cuts off the high-voltage circuit during system startup, shutdown, or fault. It has high withstand voltage (e.g., 1000V DC), high current carrying capacity (e.g., hundreds of amperes), and fast response characteristics. The main fuse 214 is connected in series in the main circuit as the last line of defense for overcurrent protection. It blows in the event of a short circuit or severe overcurrent to isolate the fault. The pre-charging circuit pre-charges the capacitor through a current-limiting resistor during system startup to avoid surge current impact caused by direct connection of high voltage.

[0238] The communication module includes an external CAN bus interface 215. The BMS communicates with the unmanned surface vessel system 20 through the external CAN bus interface 215 to upload the cell parameters, status data and alarm information of the battery pack 21, and to receive the power start and stop commands from the unmanned surface vessel system 20.

[0239] The enclosure structure provides physical protection (dustproof, waterproof, corrosionproof), isolates high-pressure and low-pressure areas, and meets fire resistance standards.

[0240] The unmanned surface vessel system 20 is configured to send power start / stop commands to the BMS via an external CAN bus to control the charging and discharging status of the battery pack 21, and to centrally display the status information of the battery pack 21 through the system display.

[0241] The external CAN bus interface is configured to use a master-slave communication protocol architecture for coordinated charging and discharging control when multiple battery packs 21 are connected in parallel.

[0242] In one possible embodiment, the communication module further includes an internal CAN bus interface 216, which is configured to communicate with external debugging equipment during the system debugging phase to update the BMS control logic.

[0243] In one possible embodiment, the built-in battery management system 211 (BMS) further includes a BMS power supply interface 217, which is used to connect to an external 12V power supply for the BMS.

[0244] When the external 12V power supply to the BMS is connected, the BMS will detect whether the battery module 212 and the high-voltage circuit are normal.

[0245] In one possible embodiment, the positive and negative terminals of the battery module 212 are connected to the main busbar 218 on the unmanned surface vessel (USV), and the main busbar 218 supplies power to all electrical equipment on the USV.

[0246] In one possible embodiment, the pre-charging circuit includes a pre-charging resistor 219, an auxiliary contactor 220, and control logic circuitry;

[0247] The resistance value of the pre-charging resistor 219 is in the range of 5Ω to 20Ω, and the engagement time of the auxiliary contactor 220 and the operation interval of the main contactor 213 are set to 100ms to 300ms to avoid current surges during the pre-charging process.

[0248] In one possible embodiment, the pre-charge circuit also includes an auxiliary fuse 225. When the peak current during pre-charge exceeds 1.2 times the rated current of the pre-charge resistor 219, the system will disconnect the auxiliary contactor 220 and trigger overcurrent protection. However, if the auxiliary contactor 220 fails to disconnect in time, or if a short circuit occurs, the auxiliary fuse 225 can serve as backup protection, melting to cut off the pre-charge circuit and preventing damage to components such as the pre-charge resistor 219 and auxiliary contactor 220 due to overcurrent, thereby ensuring the safe operation of the entire battery power system.

[0249] In one possible embodiment, the high-voltage control module further includes a high-voltage connector 221 and a busbar 222 for high-voltage electrical connection between the battery module 212 and the load. It features low impedance, high temperature resistance, and an IP67 or higher protection rating.

[0250] In one possible embodiment, the battery module 212 includes a positive battery module 223 and a negative battery module 224.

[0251] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A battery-powered control method for a new energy unmanned surface vessel, characterized in that, Includes the following steps: The unmanned surface vessel's overall system sends start / stop commands to the BMS via the external CAN bus, and the BMS connects to the external power supply to automatically wake up and start the battery pack. After the BMS starts, it detects the battery module voltage, main circuit current and temperature of key components through current and temperature sensors. If the conditions are normal, the pre-charging circuit is started, and the high-voltage circuit capacitor is pre-charged through the pre-charging resistor. After precharging is complete, the BMS disconnects the auxiliary contactor and closes the main contactor, and the battery module supplies power to the electrical equipment. During operation, the BMS collects cell parameters, charging and discharging current, SOC and temperature data in real time, and uploads them to the unmanned surface vessel's overall system for monitoring via the external CAN bus; when multiple battery packs are connected in parallel, coordinated charging and discharging control is carried out through the external CAN bus using a master-slave communication protocol architecture. The unmanned surface vessel's overall system sends a shutdown command according to a preset route or SOC threshold, and the BMS disconnects the main contactor; when overcurrent, high temperature or battery module abnormality is detected, the BMS triggers the main fuse to blow and cuts off its own power supply. Among them, real-time acquisition of cell parameters includes: real-time acquisition of individual cell voltage and total battery module voltage through BMS, and calculation of SOH through cycle count accumulation and capacity decay model; When calculating SOH using the cumulative cycle count and capacity decay model, the following is included: The number of charge-discharge cycles of the battery module is recorded in real time by the BMS. The number of charge-discharge cycles = the number of full cycles + the number of equivalent full cycles. A full cycle is defined as a single charge-discharge process with a discharge depth ≥ 80%. The number of equivalent full cycles is determined based on the number of partial cycles with a discharge depth < 80% and its discharge depth. Based on a capacity decay model that combines charge-discharge cycle count, basic decay coefficient, temperature-accelerated decay coefficient, and temperature range, the capacity of the battery module after decay is generated. Based on the battery module's degraded capacity and rated capacity, the SOH is obtained; When collecting SOC in real time, the following are included: The initial SOC value is obtained, and the charging and discharging current data collected by the current sensor is processed by a second-order low-pass filtering algorithm to calculate the average current value per unit time. The SOC value to be compensated is calculated using the current integration method based on the average current value. Temperature-dependent self-discharge compensation is performed on the SOC value to be compensated to obtain the SOC value; When obtaining the initial SOC value, the following is included: During startup, the SOC value stored in the BMS non-volatile memory before the last power failure is read first as the initial SOC value; if there is no valid data, the total voltage of the battery module is measured by the open circuit voltage method, and the initial SOC value is obtained by querying the preset OCV-SOC mapping table. When calculating the SOC value to be compensated, the following is included: Using 0.1s to 1s as the integration time interval Δt, the average current value after second-order low-pass filtering is integrated based on the current actual capacity of the battery module to obtain the SOC value to be compensated. When performing temperature-dependent self-discharge compensation, the following is included: The compensation current is determined by querying the self-discharge coefficient table pre-installed in the BMS based on the real-time temperature collected by the temperature sensor, and the SOC value to be compensated is compensated based on the compensation current and the time interval Δt.

2. The method according to claim 1, characterized in that, Pre-charging and closing the main contactor include: The high-voltage circuit capacitor voltage is monitored in real time by the control logic circuit. When the voltage reaches 90%~98% of the total voltage of the battery module, the pre-charge is determined to be completed. Then the auxiliary contactor is disconnected and the main contactor is closed after an interval of 100ms~300ms. During pre-charging, the pre-charging circuit current is collected synchronously. When the peak value exceeds 1.2 times the rated current of the pre-charging resistor, the auxiliary contactor is immediately disconnected and overcurrent protection is triggered, and a fault code is uploaded through the external CAN bus.

3. The method according to claim 1, characterized in that, When acquiring temperature data in real time via BMS, the following is included: The temperature data was acquired using at least three NTC thermistors, and the following were monitored: The cell temperature of the battery module, with sampling points covering the upper, middle and lower layers of cells within the battery module; Contact temperature of the main contactor in the high-voltage control module; Surface temperature of the capacitor in the high-voltage circuit; The temperature sampling frequency is no less than 10Hz and is compared with a preset threshold in real time. If the threshold is exceeded, a graded protection logic is triggered.

4. The method according to claim 3, characterized in that, When the graded protection logic is triggered, it includes: When the temperature reaches 55℃ or -10℃, the BMS will send an early warning via the external CAN bus, and the unmanned surface vessel's overall system will adjust the power output to 80% and start heat dissipation or preheating. When the temperature rises to 65℃ or drops to -20℃, the BMS limits the charging and discharging current to 50% of the rated value and sends a power limiting command via the external CAN bus, and the unmanned surface vessel's overall system switches to low-power cruise. When the temperature exceeds 70℃ or falls below -25℃, or when the temperature changes by more than 5℃ / s within 10 seconds, the BMS disconnects the main contactor and transmits an emergency stop signal via the external CAN bus. If the temperature does not drop after an emergency shutdown and remains above 70°C or below -25°C for 3 seconds, the BMS will trigger the main fuse to blow and isolate the high-voltage circuit.

5. The method according to claim 1, characterized in that, When performing coordinated charge and discharge control, the following are included: Designate one battery pack as the master controller and the rest as slave controllers; The main controller periodically broadcasts a synchronization clock and charging / discharging command frames via an external CAN bus. The frame structure includes the total system current requirement, voltage limit threshold, preset maximum safe operating temperature threshold, and priority identifier. After receiving instructions from the controller, the master controller feeds back its own status and dynamic parameters via the external CAN bus, and dynamically allocates the charging and discharging current of each slave controller accordingly.

6. The method according to claim 5, characterized in that, When dynamically allocating the charging and discharging current of each slave controller, the following applies: The controller feeds back SOC, SOH, maximum allowable current of the battery pack, standard deviation of battery pack voltage, and temperature safety margin through the external CAN bus. Kalman filtering algorithm is used to filter noise from SOC and SOH data and remove outliers; The comprehensive weight of each slave controller is generated based on SOC, SOH, battery pack voltage standard deviation and temperature safety margin, combined with dynamic adjustment coefficients. The basic allocation coefficients for each slave controller are generated based on the comprehensive weights; Based on the dynamic allocation coefficient of the basic allocation, the total current demand of the system, and the maximum allowable current of the battery pack, the charging and discharging current of each slave controller is allocated. When a controller approaches its current limit for several consecutive cycles, a load transfer mechanism is automatically triggered, allocating a portion of the current to other healthy battery packs.

7. A new energy unmanned surface vessel battery power control system, characterized in that, During runtime, the method of claim 1 is executed, comprising: The battery pack has a built-in BMS that integrates current and temperature sensors. The BMS is electrically connected to the battery module. The current sensor monitors the main circuit current in real time for overcurrent protection, SOC calculation, and energy management. The temperature sensor monitors the temperature of key components and triggers heat dissipation. The high-voltage control module, integrated within the battery pack, includes a main contactor, a pre-charging circuit, and a main fuse. The main contactor is electrically connected to the BMS and is responsible for controlling the on / off state of the main circuit. The main fuse is connected in series with the main circuit and melts in case of a short circuit or severe overcurrent to isolate the fault. The pre-charging circuit is electrically connected to the BMS and pre-charges the high-voltage circuit capacitor through a current-limiting resistor when the system starts up. The communication module includes an external CAN bus interface. The BMS communicates with the unmanned surface vessel (USV) system through the external CAN bus interface to upload the battery pack's cell parameters, status data, and alarm information, and to receive power start / stop commands from the USV system. The enclosure structure provides physical protection, isolating high-voltage and low-voltage areas; The external CAN bus interface is configured to use a master-slave communication protocol architecture for coordinated charging and discharging control when multiple battery packs are connected in parallel.

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