Dynamic energy compensation and power distribution method and system for rail transit storage battery charger

Abstract

The invention relates to the technical field of rail transit vehicle-mounted power supply, and discloses a dynamic energy supplement and power distribution method and system for a rail transit storage battery charger. The method comprises the following steps: initializing load equipment motor sub-scene parameters; synchronously acquiring data of a motor, a storage battery and a charger; calculating a power threshold and a current threshold; deciding an energy complementing strategy; the charger adjusts the power according to the step length, and the load equipment carries out PWM current limiting; the normal mode is recovered and the fault is processed after the fault is normal. The system comprises a parameter configuration module, a data acquisition module and the like. According to the invention, the charger is upgraded to a dual mode combining charging and dynamic energy complementation, the step length is adapted according to scenes, the service life of the storage battery is prolonged by more than 20%, the fault probability is reduced, the existing hardware is adapted, and the rail transit standard is met.

Description

Technical Field

[0001] This invention relates to the field of on-board power supply control technology for rail transit, and in particular to a dynamic energy replenishment and power distribution method and system for rail transit battery chargers, applicable to rail transit vehicles such as subways, high-speed trains, and light rails. Background Technology

[0002] In the current rail transit sector, the power supply for gate control motors and air conditioning fans in the onboard power supply systems of high-speed rail, subway, and light rail vehicles, as well as the battery chargers, generally adopt an independent operation mode.

[0003] As a load device, the starting current of the gate control motor frequently surges, leading to over-discharge of the battery and affecting its lifespan. For example, during the operation of a subway gate control system, frequent opening and closing of doors causes the gate control motor to draw high current frequently, resulting in deep discharge of the battery. In this scenario, the average annual battery degradation rate reaches 12%, and the battery replacement cycle is shortened from 1.5 years to 1.2 years, leading to increased operating costs.

[0004] As load equipment, the air conditioning fans in subways or high-speed trains experience power fluctuations of up to ±30% with a fluctuation period of 10-30 seconds under heavy summer cooling conditions. This power fluctuation must be entirely replenished by the battery, leading to increased battery charge-discharge cycles and further accelerating battery lifespan degradation. In more severe cases, this can cause the supply voltage to drop sharply from DC 110V to 85V, triggering overcurrent protection faults in the air conditioning fan inverter and impacting operational stability.

[0005] Existing LLC resonant battery chargers adjust charging power solely based on the SOC (State of Charge) collected by the BMS (Battery Management System), lacking the ability to sense motor power demand. When the gate motor starts or the air conditioner fan is under heavy load, the charger maintains a fixed charging power, failing to dynamically supplement the motor's power supply gap. This causes the power supply pressure to be completely transferred to the battery, resulting in a predicament where the high motor load leads to deep battery discharge, but the charger's lag in response prevents it from replenishing the energy in time. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a dynamic energy replenishment and power distribution method and system for rail transit battery chargers. By upgrading the charger to a dual-mode system that combines charging and dynamic energy replenishment, the power fluctuation problem of gate motors or air conditioning fans can be solved, the battery cycle life can be extended, and the probability of motor start-up failure can be reduced.

[0007] To achieve the above objectives, the present invention provides the following technical solution: According to one aspect of the present invention, a method for dynamic energy replenishment and power distribution of a rail transit battery charger is provided, comprising the following steps: S1: Based on the load device type, initialize the load device motor parameters, charger parameters, and battery safety threshold; S2: Simultaneously collect multi-dimensional data through load devices, battery management system modules, and chargers; S3: Calculate the remaining power of the charger and the motor current limit threshold based on the multi-dimensional data; S4: Determine the charger's energy replenishment strategy based on the relationship between the remaining power and the motor's peak power; S5: According to the energy replenishment strategy, the charger adjusts the energy replenishment power according to the set step size, and the load device limits the motor current to less than or equal to the motor current limit threshold through PWM modulation, thus forming a closed-loop control; S6: After the motor load of the load device ends, the normal power replenishment mode is restored. If a fault is detected, the hierarchical protection mechanism is triggered and a fault warning signal is sent.

[0008] According to one embodiment of the present invention, in step S1, the load device is a gated motor, and the load device motor parameters include the gated motor rated current and peak starting power; or, the load device is an air conditioner fan, and the load device motor parameters include the air conditioner fan rated power and peak heavy-load power; the charger parameters include: charger rated power, gated scenario power adjustment step size, and fan scenario power adjustment step size; the battery safety thresholds include: battery health state SOH protection threshold, battery charging state SOC protection threshold, and motor discharge current limit ratio.

[0009] According to an embodiment of the present invention, in step S2, the multi-dimensional data includes the motor start signal or heavy load signal of the load device, the battery health status (SOH) and charging status (SOC), and the real-time charging power of the charger; the gate controller captures the gate motor start signal through the logic control unit and collects the motor current through the current sampling unit; the air conditioner controller collects the fan power supply voltage and current through the analog quantity acquisition unit; the BMS collects the battery SOH, SOC, and real-time discharge current; and the charger collects its own real-time charging power and power factor correction (PFC) parameters.

[0010] According to one embodiment of the present invention, in step S3, the remaining power of the charger is calculated according to the formula "rated output power of the charger minus real-time charging power of the charger"; the motor current limit threshold is calculated according to the formula "rated motor current multiplied by the set limit ratio".

[0011] According to an embodiment of the present invention, in step S4, the dynamic energy replenishment strategy includes: if the remaining power of the charger is not less than the peak power of the motor, the charger fully undertakes the power demand of the motor, and the battery does not participate in the discharge; if the remaining power of the charger is less than the peak power of the motor, the charger undertakes the maximum replenishable power, and the power gap is supplied by the battery on demand.

[0012] According to an embodiment of the present invention, in step S5, when the charger adjusts the replenishment power, the output power is adjusted through a resonant circuit to maintain the output voltage stable within the fluctuation range allowed by the rail transit vehicle power supply standard; the current closed-loop control includes: real-time acquisition of motor current and feedback to the load device, dynamic adjustment of motor drive power by adjusting the PWM duty cycle, and limiting the rise slope of motor current.

[0013] According to an embodiment of the present invention, in step S6, the conventional charging and basic power replenishment mode refers to the charger reverting to an operating mode that primarily charges the battery while also considering the basic power requirements of the motor; the graded protection mechanism includes at least one of reducing the charger's power replenishment to a safe range, limiting the battery discharge current, and cutting off the power supply to non-critical loads; the fault warning signal is sent to the train control and management system via the communication bus.

[0014] According to one embodiment of the present invention, the power adjustment step size and energy replenishment logic of the charger are dynamically adapted according to the load device type: For gate control motors, a first-step long-power regulation is adopted to quickly respond to starting power requirements; For air conditioner fans, a second-step power adjustment with a length smaller than the first step is used to smoothly follow power fluctuations and avoid voltage instability caused by sudden changes in charger power. The first and second power adjustment steps are iteratively optimized by the parameter configuration module based on load data from the actual operating scenario.

[0015] According to one embodiment of the present invention, during the entire process from steps S2 to S6, the charger's power replenishment curve, motor current fluctuation data, battery SOH / SOC change trend, and operating parameters at the time of fault triggering are recorded synchronously and stored in the on-board log component; the log component supports exporting data through the train control and management system or the ground operation and maintenance platform for subsequent load characteristic analysis, battery life prediction, and power replenishment strategy optimization.

[0016] According to another aspect of the present invention, a dynamic energy replenishment and power distribution system for a rail transit battery charger is provided to implement the method described above. The system includes a parameter configuration module, a data acquisition module, a dynamic calculation module, a dynamic decision-making module, a power adjustment module, and a recovery protection module. The parameter configuration module is used to initialize the load device motor parameters, charger parameters and battery safety threshold based on the load device type. The data acquisition module is used to synchronously collect multi-dimensional data through the load device, the battery management system module, and the charger. The dynamic calculation module is used to calculate the remaining power of the charger and the motor current limit threshold based on the multi-dimensional data. The dynamic decision-making module is used to determine the charger's energy replenishment strategy based on the relationship between the remaining power and the motor's peak power. The power regulation module is used to control the charger to adjust the power of the charging according to the charging strategy by a set step size. The load device limits the motor current to less than or equal to the motor current limit threshold through PWM modulation, thus forming a closed-loop control. The recovery protection module is used to restore the device to the normal charging and basic power replenishment mode after the motor load ends. If a fault is detected, it will trigger graded protection and send an early warning.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By using a charger, a dual-mode reconfiguration of charging and dynamic energy replenishment is achieved. When the gate motor starts, the battery does not discharge, reducing the average annual SOH (State of Harm) decay rate from 12% to 9.5%, and extending cycle life from 500 cycles to 600 cycles, an improvement of ≥20%. Under heavy load, the air conditioning fan only bears a basic discharge of 5A, reducing the SOH decay rate from 10% to 8%, far exceeding the industry average. Simultaneously, the gate motor starting current is stabilized at 15A (previously 30A), and the power supply voltage fluctuation is ≤5V. The failure probability of the subway gate control system and air conditioning system is reduced by more than 87%, completely eliminating the operational risks caused by sudden current increases and voltage fluctuations.

[0018] 2. Controllable economic costs and high hardware reusability: It fully reuses Bosman's existing BSM series gate controllers, air conditioning controllers and LLC resonant chargers, and realizes the functions only through software firmware upgrades. The modification cost of a single device is ≤500 yuan, which is 99% lower than the cost of "hybrid energy storage solutions of supercapacitors and batteries", greatly reducing the company's R&D and operation and maintenance investment; the battery replacement cycle is extended from 1.2 years to 1.5 years, and the estimated annual operating cost of subway and other projects is reduced by 20%.

[0019] 3. Strong application adaptability and compliance with industry standards: It can be directly adapted to various rail transit models such as subway, high-speed rail, and light rail, supports mainstream CAN / MVB communication protocols, and complies with core standards such as EN50155 (-40℃~+85℃ environment) and IEC61508 (SIL2 / SIL3 functional safety). It can be deployed in batches without modifying the existing vehicle architecture. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a flowchart of a dynamic energy replenishment and power distribution method for rail transit battery chargers; Figure 2 This is a schematic diagram of a dynamic energy replenishment and power distribution system for a rail transit battery charger. Detailed Implementation

[0021] To facilitate a clear description of the technical solutions in the embodiments of the present invention, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect. For example, the first threshold and the second threshold are merely used to distinguish different thresholds and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" are not necessarily different.

[0022] It should be noted that in this invention, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0023] In this invention, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one" or similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, "at least one of a, b, or c" can represent: a, b, c, a combination of a and b, a combination of a and c, a combination of b and c, or a, b, and c, where a, b, and c can be single or multiple.

[0024] In existing rail transit systems, there is no power distribution coordination logic between gate controllers, air conditioning controllers, and chargers. They rely solely on their own independent protection mechanisms (such as gate controller overcurrent protection and charger overvoltage protection). When the motor suddenly experiences a high load, multiple device protection conflicts are likely to occur. For example, when the gate controller stops due to overcurrent, the charger continues to charge. The failure rate of the subway gate control system due to this type of coordination problem reaches 23%, which does not meet the high reliability requirements of rail transit operation.

[0025] The technical solution of this invention breaks through the existing mode of independent power supply for motors and passive charging of chargers. By dynamically replenishing energy to reconstruct the function of the charger, it upgrades from single charging to a dual mode combining charging and dynamic replenishment. This solves the problems of sudden increase in starting current of gate motor and power fluctuation of air conditioner fan under heavy load, thereby extending the cycle life of the battery and reducing the probability of starting failure of gate motor / air conditioner fan.

[0026] like Figure 1 The diagram shows a flowchart of a dynamic energy replenishment and power distribution method for a rail transit battery charger. The method includes the following steps: S101: Parameter Initialization Based on the load device type (gate motor or air conditioner fan), initialize three types of parameters: Load parameters: rated current and peak starting power of the gate motor; rated power and peak heavy-load power of the air conditioner fan; Charger parameters: rated power, power adjustment step size for different scenarios: 5kW / 100ms for gated scenarios and 2kW / 100ms for wind turbine scenarios; Battery safety thresholds: SOH protection threshold (set to ≥80%), SOC protection threshold (set to ≥20%), motor discharge current limit ratio (set to 1.5 times the rated current).

[0027] S102: Multi-dimensional data acquisition Data is collected synchronously from the load device, BMS module, and charger, and transmitted via CAN / MVB bus. The collected load data includes: the start signal and real-time current of the gated motor; the heavy load signal and voltage / current of the air conditioner fan; in the gated motor scenario, the response delay of the logic control unit (CPLD) in capturing the start signal is ≤10ms, and the current sampling unit (using TI INA226 chip) has a sampling frequency of 1kHz to ensure the capture of the peak start current; in the air conditioner fan scenario, the analog acquisition module (12-bit precision) collects the voltage / current, and the error in calculating the power is ≤±2%.

[0028] The collected BMS data includes: battery SOH, battery SOC, and battery real-time discharge current; The collected charger data includes: real-time charging power of the charger and PFC (power factor correction) parameters of the charger.

[0029] S103: Calculate the motor current limit threshold. The specific calculation method is as follows: Charger remaining power = Charger rated output power - Real-time charging power; Motor current limit threshold = Motor rated current × Discharge current limit ratio.

[0030] S104: Determine the energy replenishment strategy, specifically: If the remaining power is greater than or equal to the peak power of the motor: the charger fully meets the power demand of the motor, and the battery does not discharge; If the remaining power is less than the peak power of the motor: the charger can provide the maximum replenishable power, and the shortfall is supplied by the battery.

[0031] If the BMS reports that the battery SOH is less than 80%, it will automatically reduce the peak power demand of the motor. For example, the starting power limit of the gate motor will be reduced to 6kW to prioritize the protection of battery life.

[0032] S105: Closed-loop control for dynamic energy replenishment The charger adjusts the charging power in steps and maintains the voltage stable at DC110V through the LLC resonant circuit; The load device uses PWM (Pulse Width Modulation) to limit the motor current to be less than or equal to the motor current limit threshold, and dynamically adjusts the duty cycle to limit the current rise slope.

[0033] S106: Mode Recovery and Troubleshooting After the motor load ends, the charger resumes the normal charging and basic power replenishment mode, which is: charging is the main focus, while taking into account the basic power of the motor; in case of a fault, it triggers graded protection (power reduction, discharge limitation, disconnection of non-critical loads) and sends an early warning to TCMS (Train Control and Management System).

[0034] like Figure 2 The diagram shows a dynamic energy replenishment and power distribution system for a rail transit battery charger. The system, used to implement the above method, includes the following modules: The parameter configuration module 201 is used to initialize scenario-specific parameters. Based on the load device type, it initializes the load device motor parameters, charger parameters, and battery safety thresholds, and supports software upgrades and modifications. The data acquisition module 202 is used to synchronously acquire multi-dimensional data from the load, BMS, and charger, and transmit it via bus. The data acquisition module transmits data to the dynamic calculation module via CAN bus (baud rate 250kbps) or MVB bus, with a transmission delay of ≤50ms to ensure real-time performance. When the collected data is transmitted via the bus, priority marking is used: motor start / overload signal has the highest priority, and battery SOH / SOC has the second highest priority, to avoid data congestion.

[0035] The dynamic calculation module 203 is used to calculate the remaining power of the charger and the motor current limit threshold based on the multi-dimensional data. The dynamic decision module 204 is used to determine the charger's energy replenishment strategy based on the relationship between the remaining power and the peak power of the motor. If the BMS feedback shows that the battery's SOH is less than 80%, the dynamic decision module will automatically reduce the peak power demand of the motor, for example, reducing the upper limit of the starting power of the gate motor to 6kW, to prioritize the protection of battery life.

[0036] The power adjustment module 205 is used to control the charger to adjust the power of the charging step by step according to the charging strategy, and to cooperate with the load device to limit the motor current to less than or equal to the motor current limit threshold through PWM modulation to form a closed loop control. The recovery protection module 206 is used to restore the device to the normal charging and basic power replenishment mode after the motor load ends. If a fault is detected, it will trigger graded protection and send an early warning.

[0037] As a further improvement, the method can also identify the load type based on the collected data. The load type identification algorithm distinguishes between door control motors and air conditioning fans by collecting signal characteristic parameters and power or current characteristic parameters of the load device and combining them with a preset judgment threshold. The specific identification criteria are as follows: (1) If the duration of the short-time pulse start signal is ≤2s and the current increases by ≥2 times the rated value, it is determined to be a gate control motor; if the power fluctuation range of the periodic continuous heavy load signal is ≥±20% and the fluctuation period is ≥10s, it is determined to be an air conditioner fan. (2) Judgment is made using power and current characteristic parameters. The threshold for gate motor is that the peak starting power is ≥5kW and the duration is ≤2s, and the peak starting current is ≥2 times the rated current. The threshold for air conditioner fan is that the power fluctuation period is ≥10s and the fluctuation range is ≥±20%, and there is no short-term sudden increase in current (current change rate ≤0.5A / ms).

[0038] The load type identification algorithm runs on the ARM Cortex-M7 MCU (based on the FreeRTOS real-time operating system) of the parameter configuration module, and the execution flow is as follows: Data input: Receives initial load power / current data (sampling frequency 1kHz), signal duration, and BMS priority signal transmitted by the data acquisition module; Feature matching: Matches the input data with preset characteristic parameters of the gate motor / air conditioner fan. If the threshold for gated motor determination is met, mark the load type as 'gated motor' and output the gated scene step size (initial 5kW / 100ms). If the air conditioner fan detection threshold is met, mark the load type as 'air conditioner fan' and output the fan scene step size (initial 2kW / 100ms). If both thresholds (extreme operating conditions) are met simultaneously, the 'door control motor' will be matched first (door control is a safety-critical load). Step output: The determined step signal is sent to the power regulation module via the CAN bus (baud rate 250kbps), with an execution delay of ≤85ms.

[0039] The load type identification algorithm iteratively optimizes the step size based on actual operational data, and the specific rules are as follows: Collect 1000 load replenishment data, including the starting current fluctuation value of the gate motor and the heavy load power deviation value of the air conditioner fan; For gate control scenarios, if the starting current of the gate control motor fluctuates by more than ±5% (e.g., the rated 30A starting current fluctuates to more than 31.5A), the gate control scenario step size will be reduced from 5kW / 100ms by 0.5kW / 100ms until the current fluctuation is ≤±5%. For wind turbine scenarios, the step size is optimized as follows: If the heavy-load power deviation of the air conditioning fan exceeds ±3% (e.g., the target is 6.5kW but the actual supplementary power is only 6.3kW), the step size for the wind turbine scenario is increased by 0.2kW / 100ms until the power deviation is ≤±3%; Iteration cycle: Optimization is performed once every 1000 load data collections, and the optimization results are stored in the MCU's Flash memory (not lost when power is off).

[0040] The load type identification algorithm also has a dynamic threshold self-calibration function. The self-calibration trigger condition is as follows: when the algorithm makes three consecutive identification errors (such as misidentifying a light rail gate motor as an air conditioner fan), or when the train model changes (receiving a "model switching command" via TCMS), the threshold self-calibration is automatically initiated.

[0041] During the self-calibration process, characteristic parameters of the target load are first collected multiple times (e.g., 50 times), such as the duration of the start signal and the magnitude of the current surge of the light rail gate motor. Outliers are eliminated, and the upper / lower limit of the 95% confidence interval is taken as the new threshold. For example, the threshold for the start signal of the light rail gate motor is adjusted from 2s to 3s. After the new threshold is applied, if the recognition accuracy is ≥99% for 20 consecutive times, it is saved to the Flash memory of the parameter configuration module. If the accuracy is insufficient, the collection and calibration are repeated. Through rail transit load recognition, multi-model adaptation can be achieved without manual intervention, supporting 6 mainstream rail transit models including subway, high-speed rail, and light rail. This function is implemented only by optimizing the algorithm logic and reusing the existing ARM Cortex-M7 MCU hardware, solving the pain point of existing technologies requiring redevelopment of software for multi-model adaptation.

[0042] Example 1: Subway door control motor scenario (adapted to Bosman BSM unified door controller) The gate control motor uses a Bosman brushless gate control motor that is compatible with the Beijing Metro, with a rated current of 10A, a rated power of 3kW, a starting current of 30A, and a starting power of 8kW; the charger uses an LLC resonant battery charger, with an input of DC1500V (metro vehicle power supply) and an output of DC110V, with a rated power of 30kW; the BMS module uses a Bosman battery management system, compatible with DC110V lead-acid batteries (capacity 100Ah); the communication interface uses a CAN bus.

[0043] Data Acquisition: The door controller captures the door motor start signal (metro door opening command) through the CPLD, and at the same time, the current sampling circuit collects the start current (30A), calculates the start power (8kW), and sends it to the charger via the CAN bus; the BMS synchronously collects the battery SOC=60%, SOH=90%, and current discharge current=0A; After receiving the data, the charger MCU calculates the remaining power = rated power 30kW - current charging power 10kW = 20kW. Since 20kW ≥ starting power 8kW, the decision is: the charger will fully charge the battery and the battery will not discharge. The charger's charging power has been increased from 10kW to 18kW (10kW charging + 8kW supplemental power), with the output voltage stabilized at DC110V±2%; the gate controller CPLD synchronously limits the motor starting current to ≤15A (achieved through PWM modulation) to prevent sudden current surges; Once the gate motor starts (lasting 1.5s), the current drops to 10A, the power drops to 3kW, and the charger's replenishment power simultaneously drops to 3kW, returning to the mode of 10kW charging and 3kW replenishment.

[0044] When the gate motor starts, the battery does not discharge, the SOH decay rate decreases from 12% / year to 9.5% / year, and the cycle life is extended from 500 cycles to 600 cycles, meeting the target of life improvement of ≥20%; the gate motor starting current is stable at 15A, the power supply voltage fluctuation is ≤5V, and the overcurrent protection is not triggered. In the subway gate control system, this type of fault has decreased from an average of 23 times per year to 3 times, and the fault probability has been reduced by 87%, far exceeding the target of 15%.

[0045] Example 2: High-speed rail air conditioning fan scenario (adapted to Bosman BSM distributed air conditioning controller) The air conditioning fan is a high-speed rail air conditioning fan with a rated power of 5kW, a rated current of 45A, a heavy-load peak power of 6.5kW, and a fluctuation period of 20s. The charger adopts an LLC resonant battery charger with an input of 3AC380V, an output of DC110V, and a rated power of 30kW. The air conditioning controller is a Bosman BSM distributed air conditioning controller, which includes a 16-channel analog signal acquisition module and an MVB communication module. The BMS module adopts a Bosman high-speed rail dedicated BMS, which supports real-time acquisition of SOC / SOH and has an MVB communication interface.

[0046] The BSM distributed air conditioning controller detects the increase in air conditioner fan power supply current from 45A to 58A through the analog signal acquisition module, calculates the increase in power from 5kW to 6.5kW (triggered by heavy load signal), and sends the data to the charger via the MVB bus; the BMS also collects data on battery SOC=70%, SOH=85%, and current discharge current=5A. After receiving the data, the charger MCU calculates the remaining power = 30kW - current charging power 15kW = 15kW. Since 15kW ≥ peak power 6.5kW, it decides that "the charger's replenishment power follows the fluctuation of the fan power, and the battery maintains a basic discharge of 5A". The charger's replenishment power jumps from 5kW (basic replenishment) to 6.5kW, with a total output power of 15kW charging + 6.5kW replenishment = 21.5kW; the air conditioner controller synchronously adjusts the PWM duty cycle of the fan drive to limit current fluctuations to ≤±2A and avoid sudden voltage drops; When the wind turbine power drops from 6.5kW to 5kW (end of heavy load), the charger's replenishment power also drops to 5kW, resuming the basic replenishment mode, and the battery discharge current remains unchanged at 5A.

[0047] When the air conditioner fan is under heavy load, the battery only bears a basic discharge of 5A, without additional overload discharge. The average annual decay rate of SOH is reduced from 10% to 8%, and the cycle life is extended by 20%. The fan power supply voltage is stable at DC110V±3%, and the inverter overcurrent protection is not triggered. The number of such failures in the high-speed rail air conditioning system has decreased from an average of 8 times per year to 1 time, and the failure probability has been reduced by 87.5%.

[0048] Existing technologies generally consider the core function of a charger to be charging a battery. This invention reconstructs this function through software upgrades, enabling a dual-mode operation combining charging and energy replenishment. This solves the technical challenge of real-time matching between charger power regulation and motor demands. In practical implementation, synchronous control is achieved through 1kHz current sampling and 50ms bus delay matching. The technical solution of this invention can handle power adjustments in various scenarios. For gated motors, which require rapid step sizes (5kW / 100ms) to handle short-term peaks, and air conditioner fans, which require gentle step sizes (2kW / 100ms) to avoid voltage fluctuations, this invention achieves dynamic step size switching through a load type identification algorithm in the parameter configuration module.

[0049] This invention addresses the pain points of power supply for gate motors and air conditioning fans in rail transit, breaking through the existing independent power supply mode for motors and passive charging mode for chargers. Specifically: First, it reconstructs the charger function, achieving dual-mode collaboration of charging and dynamic energy replenishment for the first time, actively sensing the motor's power demand and solving the problem of lag in traditional charger response; Second, it develops a load type identification algorithm, determining the load type through a dual dimension of "signal characteristics and power / current parameters," and adapting the step size according to different scenarios (5kW / 100ms for gates, 2kW / 100ms for fans), taking into account both short-term peak and periodic fluctuation requirements. There is no similar scenario-adaptation solution in existing technologies; Third, it requires zero new hardware, reusing existing gate controller and charger hardware, and only upgrading the software, avoiding the high-cost modification of hybrid energy storage solutions. It provides a low-cost, high-reliability innovative solution for rail transit on-board power supply systems, combining technological breakthroughs and practical value.

[0050] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, disclosure, and other materials. In this specification, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple components. A single processor or other unit can implement several functions listed in the specification. While certain measures are described in different embodiments, this does not mean that these measures cannot be combined to produce good results.

[0051] Although the invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made therein without departing from the spirit and scope of the invention. Accordingly, this specification and drawings are merely illustrative of the invention and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if such modifications and modifications fall within the scope of the invention and its equivalents, the invention is also intended to include such modifications and modifications.

Claims

1. A method for dynamic energy replenishment and power distribution of a rail transit battery charger, characterized in that, Includes the following steps: S1: Based on the load device type, initialize the load device motor parameters, charger parameters, and battery safety threshold; S2: Simultaneously collect multi-dimensional data through load devices, battery management system modules, and chargers; S3: Calculate the remaining power of the charger and the motor current limit threshold based on the multi-dimensional data; S4: Determine the charger's energy replenishment strategy based on the relationship between the remaining power and the motor's peak power; S5: According to the energy replenishment strategy, the charger adjusts the energy replenishment power according to the set step size, and the load device limits the motor current to less than or equal to the motor current limit threshold through PWM modulation, thus forming a closed-loop control; S6: After the motor load of the load device ends, the normal power replenishment mode is restored. If a fault is detected, the hierarchical protection mechanism is triggered and a fault warning signal is sent.

2. The method according to claim 1, characterized in that, In step S1, the load device is a gate control motor, and the parameters of the load device motor include the rated current and peak starting power of the gate control motor; or, the load device is an air conditioner fan, and the parameters of the load device motor include the rated power and peak heavy-load power of the air conditioner fan. The charger parameters include: charger rated power, power adjustment step size for gated scenarios, and power adjustment step size for fan scenarios. The battery safety thresholds include: battery health state (SOH) protection threshold, battery charging state (SOC) protection threshold, and motor discharge current limit ratio.

3. The method according to claim 2, characterized in that, In step S2, the multi-dimensional data includes the motor start signal or heavy load signal of the load device, the battery health status (SOH) and charging status (SOC), and the real-time charging power of the charger. The gate controller captures the gate motor start signal through the logic control unit and collects the motor current through the current sampling unit; The air conditioning controller acquires the fan power supply voltage and current through an analog signal acquisition unit; The BMS collects the battery's SOH, SOC, and real-time discharge current; The charger collects its own real-time charging power and power factor correction (PFC) parameters.

4. The method according to claim 3, characterized in that, In step S3, the remaining power of the charger is calculated using the formula "charger rated output power minus charger real-time charging power"; the motor current limit threshold is calculated using the formula "motor rated current multiplied by the set limit ratio".

5. The method according to claim 4, characterized in that, In step S4, the dynamic energy replenishment strategy includes: if the remaining power of the charger is not less than the peak power of the motor, the charger will fully bear the power demand of the motor and the battery will not participate in the discharge; if the remaining power of the charger is less than the peak power of the motor, the charger will bear the maximum energy replenishment power and the power gap will be supplied by the battery on demand.

6. The method according to claim 5, characterized in that, In step S5, when the charger adjusts the power replenishment, it adjusts the output power through a resonant circuit to maintain the output voltage within the fluctuation range allowed by the rail transit vehicle power supply standard. The current closed-loop control includes: real-time acquisition of motor current and feedback to the load device, dynamic adjustment of motor drive power by adjusting PWM duty cycle, and limiting the rise rate of motor current.

7. The method according to claim 6, characterized in that, In step S6, the conventional charging and basic power replenishment mode refers to the charger reverting to an operating mode that primarily charges the battery while also taking into account the basic power requirements of the motor. The graded protection mechanism includes at least one of the following: reducing the charger's charging power to a safe range, limiting the battery discharge current, and cutting off the power supply to non-critical loads. The fault warning signal is sent to the train control and management system via the communication bus.

8. The method according to claim 1, characterized in that, The power adjustment step size and energy replenishment logic of the charger are dynamically adapted according to the load device type: For gate control motors, a first-step long-power regulation is adopted to quickly respond to starting power requirements; For air conditioner fans, a second-step power adjustment with a length smaller than the first step is used to smoothly follow power fluctuations and avoid voltage instability caused by sudden changes in charger power. The first and second power adjustment steps are iteratively optimized by the parameter configuration module based on load data from the actual operating scenario.

9. The method according to claim 1, characterized in that, The method further includes the following steps: Throughout the entire process from steps S2 to S6, the charger's replenishment power change curve, motor current fluctuation data, battery SOH / SOC change trend, and operating parameters at the time of fault triggering are recorded synchronously and stored in the vehicle log component. The log component supports exporting data through the train control and management system or the ground operation and maintenance platform for subsequent load characteristic analysis, battery life prediction and energy replenishment strategy optimization.

10. A dynamic energy replenishment and power distribution system for a rail transit battery charger, used to implement the method according to any one of claims 1 to 9, characterized in that, include: The module includes a parameter configuration module, a data acquisition module, a dynamic calculation module, a dynamic decision-making module, a power regulation module, and a recovery protection module. The parameter configuration module is used to initialize the load device motor parameters, charger parameters and battery safety threshold based on the load device type. The data acquisition module is used to synchronously collect multi-dimensional data through the load device, the battery management system module, and the charger. The dynamic calculation module is used to calculate the remaining power of the charger and the motor current limit threshold based on the multi-dimensional data. The dynamic decision-making module is used to determine the charger's energy replenishment strategy based on the relationship between the remaining power and the motor's peak power. The power regulation module is used to control the charger to adjust the power of the charging according to the charging strategy by a set step size. The load device limits the motor current to less than or equal to the motor current limit threshold through PWM modulation, thus forming a closed-loop control. The recovery protection module is used to restore the device to the normal charging and basic power replenishment mode after the motor load ends. If a fault is detected, it will trigger graded protection and send an early warning.

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