A photovoltaic power storage intelligent battery pack management system based on intelligent regulation

Abstract

The present application relates to the field of photovoltaic technology, and more particularly to a photovoltaic power storage intelligent battery pack management system based on intelligent regulation and control, comprising: a mobile battery vehicle carrying multiple independent drawer-type battery packs, with positive and negative electrode relays, connected to a bus through low-resistance copper bars, after the battery packs are connected in series, automatically conducting through a battery replacement connector and a power consumption device interface; each battery pack is configured with an independent sensor node, the data of each drawer-type battery pack is obtained through the sensor node, each node is connected in series through a twisted shielded wire, and multi-node communication is realized based on a CAN protocol; according to real-time power consumption requirements, a greedy algorithm is used to dynamically select the optimal drawer-type battery pack combination, and a BMS host controls the switching state of molded case switches, air switches and relay arrays according to the decision result; an emergency stop protection mechanism is provided, including DI1 and DO2. Each drawer-type battery pack is an independent energy storage unit, facilitating maintenance, repair and replacement of a single battery pack without affecting the work of other battery packs.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photovoltaic technology, in particular to a photovoltaic power storage intelligent battery pack management system based on intelligent regulation. BACKGROUND

[0002] With the acceleration of the transformation of global energy structure towards clean and low-carbon, photovoltaic power generation, as a core renewable energy technology, its installed capacity continues to grow. The photovoltaic power storage battery car, as a mobile energy storage unit in the photovoltaic power storage integrated system, emerges as the times require. It can realize flexible transportation and distribution of electric energy and can be widely used in emergency power supply, distributed energy access, remote area power supply and other scenarios.

[0003] The photovoltaic power storage battery car converts the solar energy absorbed by photovoltaic into electric energy and stores it in the battery pack in the battery car. The truck is used to transport it to the power consumption warehouse. The power consumption warehouse is a core terminal facility integrating power reception and distribution function, which provides stable power support for surrounding areas, industrial equipment, public facilities, etc. When the photovoltaic power storage battery car and the power consumption warehouse work together, the automatic plug-in device equipped in the power consumption warehouse can realize fast and accurate docking. The photovoltaic electric energy transported by the battery car can meet the needs of the self energy storage unit after being converted by the power consumption warehouse, and can also supply power to the surrounding load through the output port, forming a closed loop system of "mobile energy storage - fixed energy supply", which effectively improves the flexibility and sustainability of power supply.

[0004] However, the existing photovoltaic power storage battery car still faces many challenges in practical application, one of the key problems is the charge and discharge management of the battery pack, which is specifically manifested in:

[0005] 1. Difficulty in dynamically adapting to grid load fluctuations: During peak load, the battery energy storage system may have insufficient capacity or over-discharge, leading to power interruption or shortened equipment life; during low load period, fixed energy storage configuration is easy to cause equipment idle, causing resource waste.

[0006] 2. Shortened battery life: The battery cycle life is limited by unreasonable charge and discharge strategy, which further increases the comprehensive cost. SUMMARY

[0007] The present application provides a photovoltaic power storage intelligent battery pack management system based on intelligent regulation to solve the technical problems in the prior art.

[0008] The technical solution of the present application to solve the above technical problems is as follows: a photovoltaic power storage intelligent battery pack management system based on intelligent regulation, comprising:

[0009] Battery pack module: the mobile battery car is equipped with multiple independent drawer type battery packs, with positive and negative electrode relays, connected to the bus through low resistance copper bars, and the battery packs are automatically connected in series through the battery replacement connector and the power consumption equipment interface.

[0010] Data acquisition and transmission module: each battery pack is configured with an independent sensor node, the data of each drawer-type battery pack is obtained through the sensor node, each node is connected in series through twisted shielded wire, and multi-node communication is realized based on a CAN protocol;

[0011] BMS host control module: according to real-time power demand, an optimal drawer-type battery pack combination is dynamically selected by using a greedy algorithm, and the BMS host controls the switching states of the molded case switch, the air switch and the relay array according to a decision result;

[0012] Protection module: an emergency stop protection mechanism is provided, including DI1 and DO2, when the DI1 detects an emergency stop signal, the DO2 outputs a high level to light a fault lamp, and simultaneously sends a CAN emergency stop frame to all drawer-type battery packs to rapidly cut off the connection between the battery packs and the charging and discharging circuit.

[0013] In a preferred embodiment, the battery pack module converts solar energy absorbed by photovoltaics into electrical energy and stores the electrical energy in drawer-type battery packs in a mobile battery vehicle. The mobile battery vehicle is equipped with multiple drawer-type battery packs, each of which is an independent energy storage power supply. Each drawer-type battery pack is independently configured with a charging relay and a discharging relay. The relay coil is controlled by a BMS host through an ULN2803 driving chip. The signal is optically coupled and isolated to prevent strong electrical interference. The main circuit is connected to the central busbar using low-resistance copper bars to realize the convergence and distribution of electrical energy. A pre-charging relay and a pre-charging resistor are configured. When the switch is closed, the pre-charging resistor limits the inrush current. When the P+ end voltage reaches 90% of the battery voltage, the pre-charging relay is disconnected, and the positive relay is closed to ensure shockless access.

[0014] In a preferred embodiment, the data acquisition and transmission module connects the input end of the high-precision voltage transmission line to the positive and negative poles of each drawer-type battery pack. A four-wire connection method is used to separate the power line and the signal line to reduce the voltage division error caused by line resistance. The input end of the voltage sensor is connected to the positive / negative terminal of the battery pack. The output signal is connected to the signal conditioning chip through the RC filter circuit. The output voltage range is adjusted to 0-3.3V compatible with the BMS host ADC channel through the gain resistor. The Hall current sensor magnetic core is inserted through the charging and discharging circuit copper bar of the battery pack to ensure that the current direction is consistent with the sensor direction. The analog signal output by the Hall current sensor is connected to the ADC channel of the BMS host. The CAN_H and CAN_L signal lines of each sensor node are connected in series with twisted shielded wire. A 120 Terminal resistance, intermediate node is not connected to the resistance, in the BMS host side CAN interface adds high-speed optical coupling isolation, improve anti-interference ability, ensure that all nodes common ground, using isolated power supply for sensor power supply, avoid ground loop interference, unified all sensor node baud rate, for each sensor node is assigned a unique CAN ID, through the BMS host CAN controller realizes the arbitration of multiple nodes, using CAN analyzer in both ends of the bus injection test frame, monitor node response time, in the BMS host end compared with sensor measured value and CAN transmission value, ensure that the voltage error is less than ± 0.5%, the collected voltage, current data sliding average, eliminate noise interference, set threshold, when detecting abnormal value is marked and removed, for voltage data, set the collected voltage value V, rated voltage , voltage threshold upper limit , voltage threshold lower limit , when V> < marked as abnormal value and removed, when , keep the data, for current data, set the collected current value , rated voltage , voltage threshold upper limit , voltage threshold lower limit , when > < marked as abnormal value and removed, when , keep the data, in the battery pack static state, using open circuit voltage method according to the voltage value table to obtain the initial SOC, real-time acquisition of drawer type battery pack charge and discharge current , determine the rated capacity of drawer type battery pack , according to the charge and discharge state of drawer type battery pack to determine the charge and discharge efficiency , using ampere hour integral method to calculate the initial SOC, the specific calculation formula is as follows:

[0015] ;

[0016] wherein, represent the state of charge at time t, represent the initial state of charge at time , represent the rated capacity of the battery, represent the current value at discrete time , represents the time interval between two adjacent discrete time instants, k represents the index of the current time step, the voltage detection is started, the open circuit voltage method is triggered every 5 minutes to correct the SOC, when the correction process is triggered, the calculation of the ampere-hour integration method is suspended, the open circuit voltage of the drawer battery pack is measured, the new SOC value is obtained by table lookup, and the new SOC value is used as the new initial value of the ampere-hour integration method , the ampere-hour integration calculation is continued, and the charging and discharging efficiency is adjusted according to the battery temperature , the actual capacity of the battery is updated periodically through full charging and discharging cycles .

[0017] In a preferred embodiment, the BMS host control module monitors the P+ terminal voltage in real time through a voltage dividing resistor network composed of pull-up resistor R1 and pull-down resistor R2, calculates the actual voltage value according to the voltage dividing principle, and sets the voltage dividing resistor network to be composed of pull-up resistor and pull-down resistor The voltage monitored by the BMS host is The calculation formula of the actual voltage value is as follows:

[0018] ;

[0019] The voltage dividing signal is connected to the BMS host 12-bit ADC channel through an RC filter circuit, and the monitored P+ terminal voltage and battery voltage are continuously compared, when the P+ terminal voltage reaches 90% of the battery voltage, the BMS host controls the switching state of the related relays through the ULN2803 drive chip and the optocoupler isolation circuit, disconnects the main relay and closes the trickle charging relay during charging, triggers the DO2 port to light the yellow warning lamp and sends the status signal through the CAN bus during discharging, and communicates with external devices through the RS485 interface to obtain the power demand data in real time, analyzes the power scene through the built-in CAN controller of STM32F407, in the low-power scene, reads the SOC and single cell voltage data of each battery pack from the CAN bus through the greedy algorithm, selects the drawer battery pack with > 90% and voltage difference threshold = 1%, and preferentially activates the first 1-2 groups, in the high-power scene, selects the battery pack with > 70%, wherein represents the SOC threshold for battery pack selection in the low-power scene, monitors the charging and discharging loop current through the Hall current sensor, and distributes the load current according to the calculation result of , and the discharging relays of each battery pack are controlled by the BMS theme through independent optocoupler isolation channels to ensure synchronous response.

[0020] Low-power demand scene: the BMS host retrieves the SOC data and single cell voltage data of each drawer battery pack, selects >90% and voltage difference threshold For a drawer-type battery pack with a capacity of 1%, a greedy algorithm is used to prioritize battery packs with high capacity and stable voltage. Let there be a total of n battery packs. The state of charge of each battery pack is The average voltage of a single cell is Calculate the average voltage of all drawer-type battery packs. The specific calculation formula is as follows:

[0021] ;

[0022] in, This represents the average voltage of the drawer-type battery pack, and filters out those that meet the criteria. > And| |< The battery packs, which constitute the candidate set CAND, are used to select each candidate pack. (j Define a comprehensive evaluation value. This is used to measure its priority as a discharge combination, taking into account the historical usage count of the drawer-type battery pack. Health status The specific formula for calculating the comprehensive evaluation value is as follows:

[0023] ;

[0024] in, , This represents the weighting coefficient. The weights are adjusted according to actual needs to balance the impact of historical usage frequency and health status. A comprehensive evaluation value is selected from the candidate set CAND. The top 1-2 battery packs are used as discharge combinations;

[0025] High-power demand scenario: Assume there are n battery packs in total. The state of charge threshold for high-power scenarios is set as follows: >70% of those that meet the criteria were selected. > The drawer-type battery packs form a discharge assembly (DISCH). After determining the discharge assembly (DISCH), to ensure coordinated discharge of each drawer-type battery pack, the output current of each battery pack must be distributed according to a certain ratio. Let the total load current requirement be... The discharge combination set DISCH contains m battery packs, and the maximum output current capability of the k-th battery pack is: Then the current allocated to the k-th battery pack The specific calculation formula is as follows:

[0026] ;

[0027] The corresponding current control signal is sent to each drawer-type battery pack via the CAN bus to achieve coordinated discharge and meet the high power demand.

[0028] Based on the determined drawer-type battery pack combination decision, the BMS host sends control commands to the molded case switch, circuit breaker, and relay array. Upon receiving the command, the positive and negative relays corresponding to the target drawer-type battery pack close, connecting the target drawer-type battery pack to the charging and discharging circuit. The relays of non-target drawer-type battery packs remain open to isolate them from the charging and discharging circuit. The BMS host continuously monitors the operating status of each drawer-type battery pack, including current, voltage, and temperature parameters. If an abnormality is detected, the BMS host promptly adjusts the drawer-type battery pack combination and disconnects the faulty drawer-type battery pack to ensure the safe and stable operation of the system.

[0029] In a preferred embodiment, the DI1 port of the protection module is connected to the digital input channel of the BMS host via a normally closed emergency stop button, with 10kΩ connected in parallel across the two ends of the button. Pull-up resistors are used, and the wiring employs twisted-pair shielded cable. When the emergency stop button is pressed, the contacts open, causing the voltage at the DI1 port to rise to a high level, triggering the STM32F407's internal EXTI interrupt. The trigger time is recorded by a hardware timer, and the following circuit logic is executed immediately:

[0030] The DO2 port outputs a high-level signal through the driver circuit, driving the fault indicator light and buzzer. Simultaneously, it sends an emergency stop frame to the CAN bus via a high-speed optocoupler isolation module. The CAN bus uses two-wire differential transmission, and the host side is configured with 120... Termination resistors and ESD protection devices ensure that the shutdown command is within 50°C. Internal transmission to all battery packs;

[0031] Each drawer-type battery pack's positive and negative relays are equipped with auxiliary normally open contacts. One end of the contact is connected to a +5V power supply, and the other end is connected to a 1kV power supply. A current-limiting resistor is connected to the BMS host DI port. When the relay is closed, the contact is on and the DI port level is pulled low. When the relay is open, the contact is off and the DI port is maintained at a high level through a pull-up resistor. The BMS host scans the DI status through the GPIO port at a 100ms cycle to simulate the 12C protocol and compares the command status with the actual status. If the relay command for a certain battery pack is to be open but the DI port remains at a low level, it is determined to be a contact sticking fault. The host immediately sends a second disconnect command through the hardware redundancy channel and triggers the solid-state relay to cut off the power supply circuit of the battery pack.

[0032] Fault location is achieved through an address encoding circuit: each battery pack's DI port is connected in series with an 8-bit DIP switch. When the BMS host reads the DI status, it synchronously parses the address information, highlights the location of the faulty battery pack on the display screen, and sends a fault code to the EMS via the RS485 bus. After receiving the code, the EMS sends an alarm message containing GPS location information to the maintenance personnel via the TCP / IP protocol.

[0033] The beneficial effects of this invention are as follows: Each drawer-type battery pack is an independent energy storage unit equipped with positive and negative relays, allowing for independent control of charging and discharging. This facilitates maintenance, repair, and replacement of individual battery packs without affecting the operation of other battery packs. It also supports flexible addition, removal, and expansion of battery packs to adapt to different energy storage needs. The connection between the low-resistance copper busbar and the central bus significantly reduces energy loss during transmission, improving energy transfer efficiency. The automatic conduction design between the sliding electrical contacts on the battery vehicle chassis and the power compartment interface facilitates and automates power transmission, reducing manual operation and improving efficiency. This is based on an optimized drawer-type battery pack combination strategy. The system can dynamically select the optimal battery pack combination based on real-time power demand. When power demand is low, it prioritizes the use of high-capacity and voltage-stable battery packs to reduce the number of charge-discharge cycles for low-capacity batteries. When power demand is high, it quickly activates the appropriate battery pack to ensure reasonable energy allocation and efficient utilization, thereby improving the overall energy efficiency of the system and reducing operating costs. The emergency stop protection mechanism can quickly output a high level to illuminate the fault light when an emergency stop signal is detected, and send an emergency stop frame to all drawer-type battery packs via the CAN bus to quickly disconnect the battery pack from the charging and discharging circuit. The short response time can effectively prevent safety accidents and ensure the safety of personnel and equipment. Attached Figure Description

[0034] Figure 1 This is a flowchart of the present invention;

[0035] Figure 2 This is a system block diagram of the present invention;

[0036] Figure 3 This is a circuit diagram for reading the magnitude of the main circuit current according to the present invention;

[0037] Figure 4 This is the logic circuit diagram for determining whether a relay is switched on or off according to the present invention.

[0038] Figure 5 This is a circuit diagram for controlling an external relay switch according to the present invention;

[0039] Figure 6 This is a circuit diagram for measuring the P+ voltage according to the present invention;

[0040] Figure 7 This is a diagram of the RS485 bus of the present invention. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0042] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0043] In the description of this application, the term "for example" is used to mean "used as an example, illustration, or description." Any embodiment described as "for example" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0044] like Figure 1 This embodiment provides: a photovoltaic energy storage intelligent battery pack management system based on intelligent control, comprising:

[0045] Battery module: The mobile battery vehicle is equipped with multiple independent drawer-type battery packs, with positive and negative relays, and connected to the bus via low-resistance copper busbars. After the battery packs are connected in series, they are automatically connected to the interface of the power equipment via the battery swapping connector.

[0046] In this embodiment, the battery pack module needs to be specifically described. This module converts solar energy absorbed by the photovoltaic system into electrical energy and stores it in drawer-type battery packs within the mobile battery vehicle. The mobile battery vehicle is equipped with multiple drawer-type battery packs, each serving as an independent energy storage power source. Each drawer-type battery pack is independently equipped with a charging relay and a discharging relay. The relay coils are controlled by the BMS host via a ULN2803 driver chip. The signals are optocoupled to prevent strong electrical interference. The main circuit uses a low-resistance copper busbar connected to the central busbar to achieve energy aggregation and distribution. A pre-charge relay and a pre-charge resistor are configured. During closing, the pre-charge resistor limits the surge current. When the voltage at the P+ terminal reaches 90% of the battery voltage... Figure 7 Disconnect the pre-charge relay and close the positive relay to ensure a shock-free connection.

[0047] Data acquisition and transmission module: Each battery pack is equipped with an independent sensor node, which acquires data from each drawer-type battery pack. The nodes are connected in series via twisted-pair shielded wires and multi-node communication is achieved based on the CAN protocol.

[0048] In this embodiment, the data acquisition and transmission module needs to be specifically described. This module connects the input end of the high-precision voltage transmission line in parallel to the positive and negative terminals of each individual battery cell in the drawer-type battery pack. A four-wire connection method (two power lines VCC / GND + two signal lines S+ / S-) is used to separate the power and signal lines, reducing voltage division errors caused by line resistance. The input end of the voltage sensor is connected to the positive / negative terminals of the battery pack. The output signal is fed into the signal conditioning chip via an RC filter circuit. The output voltage range is adjusted to 0-3.3V, compatible with the BMS host ADC channel, through a gain resistor. The Hall current sensor core is passed through the copper busbar of the battery pack's charging and discharging circuit, ensuring the current direction is consistent with the direction marked on the sensor. The analog signal output from the Hall current sensor is connected to the BMS host's ADC channel. The CAN_H and CAN_L signal lines of each sensor node are connected in series using twisted-pair shielded wire. A 120V cable is connected in parallel at each of the first and last nodes of the CAN bus. Termination resistors are used, but no resistors are connected to intermediate nodes. High-speed optocoupler isolation is added to the CAN interface on the BMS host side to improve anti-interference capability, ensuring all nodes share a common ground. Isolated power supplies are used to power the sensors to avoid ground loop interference. The baud rate of all sensor nodes is unified, and a unique CAN ID is assigned to each sensor node. Multi-node arbitration is implemented through the CAN controller of the BMS host. Test frames are injected at both ends of the bus using a CAN analyzer to monitor node response time. The measured values ​​of the sensors are compared with the CAN transmission values ​​at the BMS host side to ensure that the voltage error is less than ±0.5%. A moving average is performed on the collected voltage and current data to eliminate noise interference. A threshold is set (e.g., voltage exceeding the rated range by ±20%). When an abnormal value is detected, it is marked and removed. For voltage data, let the collected voltage value be V, and the rated voltage be... The upper limit of the voltage threshold is The lower limit of the voltage threshold is When V > < When it is marked as an outlier and removed, At that time, retain the data. For current data, let the collected current value be... Rated voltage is The upper limit of the voltage threshold is The lower limit of the voltage threshold is ,when > < When it is marked as an outlier and removed, During this period, data is retained. With the battery pack in a static state, the initial SOC is obtained by looking up the voltage value in a table using the open-circuit voltage method. The charging and discharging current of the drawer-type battery pack is also acquired in real time. Determine the rated capacity of the drawer-type battery pack. The charge / discharge efficiency is determined based on the charge / discharge state of the drawer-type battery pack. The initial SOC is calculated using the ampere-hour integration method, and the specific calculation formula is as follows:

[0049] ;

[0050] in, This represents the state of charge at time t. Indicates the initial time. The state of charge, Indicates the battery's rated capacity. Indicates at discrete time The current value, This represents the time interval between two adjacent discrete moments, where k represents the index of the current time step. Timing and voltage detection are initiated, triggering an open-circuit voltage method SOC correction process every 5 minutes. When the correction process is triggered, the ampere-hour integration method calculation is paused, the open-circuit voltage of the drawer-type battery pack is measured, and the new SOC value is obtained by looking up a table, serving as the new initial value for the ampere-hour integration method. Continue performing ampere-hour integral calculations and adjust the charge / discharge efficiency based on battery temperature. The actual capacity of the battery is updated periodically through complete charge-discharge cycles. .

[0051] It should be noted that the upper limit of the voltage threshold is The lower limit of the voltage threshold is .

[0052] It should be noted that multi-node arbitration is implemented through the non-destructive bit arbitration mechanism of the CAN controller. The CAN bus adopts an arbitration rule that dominant bits take precedence over recessive bits. When multiple nodes send data at the same time, the message ID is compared bit by bit. The message with more dominant bits in the ID gains bus control, and the node with recessive bits automatically backs off, without the need for bus conflict handling.

[0053] BMS host control module: Based on real-time power demand, it uses a greedy algorithm to dynamically select the optimal drawer-type battery pack combination. The BMS host controls the switching status of the molded case switch, circuit breaker and relay array according to the decision result.

[0054] In this embodiment, the BMS host control module needs to be specifically described. The BMS host control module monitors the P+ terminal voltage in real time through a voltage divider network composed of pull-up resistors R1 and pull-down resistors R2, and calculates the actual voltage value according to the voltage divider principle. Let the voltage divider network consist of pull-up resistors R1 and R2... and pull-down resistors Composition, the voltage monitored by the BMS host is Then the actual voltage value The calculation formula is as follows:

[0055] ;

[0056] The voltage divider signal is fed into the 12-bit ADC channel of the BMS host via an RC filter circuit. It continuously compares the monitored P+ terminal voltage with the battery voltage. When the P+ terminal voltage reaches 90% of the battery voltage, the BMS host controls the switching states of relevant relays through the ULN2803 driver chip and optocoupler isolation circuit. During charging, the main relay is disconnected and the trickle charging relay is closed. During discharging, the DO2 port is triggered to illuminate the yellow warning light, and a status signal is sent via the CAN bus. The BMS host communicates with external devices via the RS485 interface to obtain real-time power demand data. After analysis by the STM32F407's built-in CAN controller, the power scenario is determined: In the low-power scenario, a greedy algorithm is used to read the SOC and individual cell voltage data of each battery pack from the CAN bus and filter out... >90% and voltage difference threshold For drawer-type battery packs with a capacity of 1%, prioritize activating the first 1-2 packs. In high-power scenarios, select... >70% of the battery pack, of which This indicates the SOC threshold for battery packs to participate in activation screening in low-power scenarios. The charging and discharging circuit current is monitored by a Hall current sensor, and the threshold is set according to... The calculation results are used to allocate the load current, and the discharge relays of each battery pack are controlled by the BMS main body through an independent optocoupler isolation channel to ensure synchronous response.

[0057] It should be noted that the circuit design integrates multiple protection mechanisms: overvoltage protection, undervoltage protection, and surge suppression. Additionally, 120V AC voltage is configured at both the beginning and end nodes of the CAN bus. Termination resistors, an ADuM1200 optocoupler isolation module added to the host side, and 10 resistors connected in parallel at the power supply end. Electrolytic capacitors and 100nF ceramic capacitors ensure stable operation of the charging and discharging control circuit in a strong electromagnetic environment, achieving precise control and safety protection.

[0058] Low-power application scenarios: The BMS host retrieves the SOC data and individual cell voltage data of each drawer-type battery pack and filters them out. >90% and voltage difference threshold For a drawer-type battery pack with a capacity of 1%, a greedy algorithm is used to prioritize battery packs with high capacity and stable voltage. Let there be a total of n battery packs. The state of charge of each battery pack is The average voltage of a single cell is Calculate the average voltage of all drawer-type battery packs. The specific calculation formula is as follows:

[0059] ;

[0060] in, This represents the average voltage of the drawer-type battery pack, and filters out those that meet the criteria. > And| |< The battery packs, which constitute the candidate set CAND, are used to select each candidate pack. (j Define a comprehensive evaluation value. This is used to measure its priority as a discharge combination, taking into account the historical usage count of the drawer-type battery pack. Health status The specific formula for calculating the comprehensive evaluation value is as follows:

[0061] ;

[0062] in, , This represents the weighting coefficient. The weights are adjusted according to actual needs to balance the impact of historical usage frequency and health status. A comprehensive evaluation value is selected from the candidate set CAND. The top 1-2 battery packs are used as discharge combinations;

[0063] High-power demand scenario: Assume there are n battery packs in total. The state of charge threshold for high-power scenarios is set as follows: >70% of those that meet the criteria were selected. > The drawer-type battery packs form a discharge assembly (DISCH). After determining the discharge assembly (DISCH), to ensure coordinated discharge of each drawer-type battery pack, the output current of each battery pack must be distributed according to a certain ratio. Let the total load current requirement be... The discharge combination set DISCH contains m battery packs, and the maximum output current capability of the k-th battery pack is: Then the current allocated to the k-th battery pack The specific calculation formula is as follows:

[0064] ;

[0065] The corresponding current control signal is sent to each drawer-type battery pack via the CAN bus to achieve coordinated discharge and meet the high power demand.

[0066] Based on the determined drawer-type battery pack combination decision, the BMS host sends control commands to the molded case switch, circuit breaker, and relay array. Upon receiving the command, the positive and negative relays of the target drawer-type battery pack close, connecting the target drawer-type battery pack to the charging and discharging circuit. The relays of non-target drawer-type battery packs remain open to isolate them from the charging and discharging circuit. The BMS host continuously monitors the operating status of each drawer-type battery pack, including current, voltage, and temperature parameters. If an abnormality is detected (such as excessive current or excessive temperature of a drawer-type battery pack), the BMS host promptly adjusts the drawer-type battery pack combination and disconnects the faulty drawer-type battery pack to ensure the safe and stable operation of the system.

[0067] It should be noted that prioritizing high-capacity and stable-voltage battery packs is because in low-power scenarios, the power demand per charge is relatively small. Prioritizing batteries with sufficient capacity can reduce the number of frequent charge and discharge cycles of low-capacity batteries, thereby reducing battery wear. At the same time, small voltage differences can ensure stable discharge processes, reducing lifespan loss caused by imbalances within the battery pack. By gradually achieving the goal of balanced overall battery pack lifespan through local optimization, we can achieve this goal.

[0068] Protection module: It is equipped with an emergency stop protection mechanism, including DI1 and DO2. When DI1 detects an emergency stop signal, DO2 outputs a high level to light up the fault light, and at the same time sends a CAN emergency stop frame to all drawer-type battery packs to quickly disconnect the battery packs from the charging and discharging circuit.

[0069] In this embodiment, it is important to note the protection module. The DI1 port of the protection module is connected to the digital input channel of the BMS host via a normally closed emergency stop button, with 10kΩ connected in parallel across the two ends of the button. Pull-up resistors (to ensure DI1 port is low under normal conditions), and the wiring uses twisted-pair shielded cable. When the emergency stop button is pressed, the contacts open, causing the voltage at DI1 port to rise to a high level, triggering the STM32F407's internal EXTI interrupt. The trigger time is recorded by a hardware timer, and the following circuit logic is executed immediately:

[0070] The DO2 port outputs a high-level signal through a driver circuit (composed of NPN / PNP transistors) to drive the fault indicator light and buzzer. Simultaneously, it sends an emergency stop frame to the CAN bus via a high-speed optocoupler isolation module. The CAN bus uses two-wire differential transmission, and the host side is configured with 120... Termination resistors and ESD protection devices ensure that the shutdown command is within 50°C. Internal transmission to all battery packs;

[0071] Each drawer-type battery pack's positive and negative relays are equipped with auxiliary normally open contacts. One end of the contact is connected to a +5V power supply, and the other end is connected to a 1kV power supply. A current-limiting resistor is connected to the BMS host DI port. When the relay is closed, the contacts are on and the DI port level is pulled low. When the relay is open, the contacts are off and the DI port is maintained at a high level through a pull-up resistor. The BMS host scans the DI status through the GPIO port to simulate the 12C protocol at a 100ms cycle and compares the command status with the actual status. If the relay command for a certain battery pack is to be open but the DI port remains at a low level, it is determined to be a contact sticking fault. The host immediately sends a second disconnect command through the hardware redundancy channel (independent CAN controller) and triggers the solid-state relay to cut off the power supply circuit of the battery pack.

[0072] Fault location is achieved through an address encoding circuit: each battery pack's DI port is connected in series with an 8-bit DIP switch. When the BMS host reads the DI status, it synchronously parses the address information, highlights the location of the faulty battery pack on the display screen, and sends a fault code to the EMS via the RS485 bus. After receiving the code, the EMS sends an alarm message containing GPS location information to the maintenance personnel via the TCP / IP protocol.

[0073] It should be noted that the circuit design integrates a power monitoring module, which forcibly triggers emergency stop logic when the BMS host power supply voltage is lower than 4.5V to prevent control failure caused by power supply issues. All digital input ports are equipped with TVS diodes to suppress surge voltage and ensure that the protection circuit operates reliably in a computing environment.

[0074] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0075] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0076] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0077] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0078] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0079] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0080] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A photovoltaic energy storage intelligent battery pack management system based on intelligent control, characterized in that, include: Battery module: The mobile battery vehicle is equipped with multiple independent drawer-type battery packs, with positive and negative relays, and connected to the bus via low-resistance copper busbars. After the battery packs are connected in series, they are automatically connected to the interface of the power equipment via the battery swapping connector. Data acquisition and transmission module: Each battery pack is equipped with an independent sensor node, which acquires data from each drawer-type battery pack. The nodes are connected in series via twisted-pair shielded wires and multi-node communication is achieved based on the CAN protocol. BMS host control module: Based on real-time power demand, it dynamically selects the optimal drawer-type battery pack combination using a greedy algorithm. In low-power scenarios, it reads the SOC and individual cell voltage data of each battery pack from the CAN bus using a greedy algorithm, and sets the state of charge threshold for low-power scenarios as follows. >90% and voltage difference threshold =1% of drawer-type battery packs, filter out those that meet the conditions. > And| |< The battery pack, of which, Indicates the average voltage of a single cell. The average voltage of the drawer-type battery packs was used to select the top 1-2 battery packs as the discharge combination based on the comprehensive evaluation value, which was based on the historical usage count of the drawer-type battery packs. and health status What was obtained This represents the SOC threshold for battery packs to participate in activation screening in low-power scenarios; In high-power scenarios, the state of charge threshold is set as follows: >70% of those that meet the criteria were selected. > The drawer-type battery pack, in which, This represents the SOC threshold for battery packs to participate in activation screening under high-power scenarios. The charging and discharging circuit current is monitored using a Hall current sensor, and the current allocated to the k-th battery pack is obtained based on the maximum output current capability of each battery pack. ,according to The calculation results are used to allocate the load current. The discharge relays of each battery pack are controlled by the BMS host through an independent optocoupler isolation channel. The BMS host controls the switching status of the molded case switch, circuit breaker and relay array according to the decision results. Protection module: It is equipped with an emergency stop protection mechanism, including DI1 and DO2. When DI1 detects an emergency stop signal, DO2 outputs a high level to light up the fault light, and at the same time sends a CAN emergency stop frame to all drawer-type battery packs to quickly disconnect the battery packs from the charging and discharging circuit.

2. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 1, characterized in that, The battery module converts solar energy absorbed by the photovoltaic system into electrical energy and stores it in a drawer-type battery pack inside the mobile battery vehicle. The mobile battery vehicle is equipped with multiple drawer-type battery packs, each of which is an independent energy storage power source. Each drawer-type battery pack is independently equipped with a charging relay and a discharging relay. The relay coil is controlled by the BMS host through a ULN2803 driver chip, and the signal is optocoupled to prevent strong electrical interference. The main circuit uses a low-resistance copper busbar connected to the central bus to realize the collection and distribution of electrical energy. A pre-charge relay and a pre-charge resistor are configured. When the circuit is closed, the pre-charge resistor limits the surge current. When the voltage at the P+ terminal reaches 90% of the battery voltage, the pre-charge relay is disconnected and the positive relay is closed to ensure impact-free connection.

3. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 1, characterized in that, The data acquisition and transmission module connects the input of the high-precision voltage transmission line in parallel to the positive and negative terminals of each individual cell in the drawer-type battery pack. A four-wire connection method is used to separate the power and signal lines, reducing voltage division errors caused by line resistance. The input of the voltage sensor is connected to the positive and negative terminals of the battery pack. The output signal is fed into a signal conditioning chip via an RC filter circuit. Gain resistors adjust the output voltage range to 0-3.3V, compatible with the BMS host ADC channel. The Hall current sensor core passes through the copper busbar of the battery pack's charging and discharging circuit. The analog signal output from the Hall current sensor is connected to the BMS host's ADC channel. The CAN_H and CAN_L signal lines of each sensor node are connected in series using twisted-pair shielded wire. A 120V parallel connection is added at each end of the CAN bus. Termination resistors are used, but no resistors are connected to intermediate nodes. High-speed optocoupler isolation is added to the CAN interface on the BMS host side to ensure all nodes share a common ground. Isolated power supplies are used to power the sensors. The baud rate of all sensor nodes is standardized. A unique CAN ID is assigned to each sensor node. Multi-node arbitration is implemented through the CAN controller on the BMS host. Test frames are injected at both ends of the bus using a CAN analyzer to monitor node response time. The measured sensor values ​​are compared with the CAN transmission values ​​on the BMS host side to ensure voltage error is less than ±0.5%. A moving average is performed on the collected voltage and current data to eliminate noise interference. A threshold is set, and outliers are marked and removed. For voltage data, let the collected voltage value be V, and the rated voltage be... The upper limit of the voltage threshold is The lower limit of the voltage threshold is When V > < When it is marked as an outlier and removed, At that time, retain the data. For current data, let the collected current value be... Rated voltage is The upper limit of the voltage threshold is The lower limit of the voltage threshold is ,when > < When it is marked as an outlier and removed, At that time, retain the data.

4. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 3, characterized in that, With the battery pack in a static state, the initial SOC is obtained by looking up the voltage value in a table using the open-circuit voltage method, and the charging and discharging current of the drawer-type battery pack is obtained in real time. Determine the rated capacity of the drawer-type battery pack. The charge / discharge efficiency is determined based on the charge / discharge state of the drawer-type battery pack. The initial SOC is calculated using the ampere-hour integration method, and the specific calculation formula is as follows: ; in, This represents the state of charge at time t. Indicates the initial time. The state of charge, Indicates the battery's rated capacity. Indicates at discrete time The current value, This represents the time interval between two adjacent discrete moments, where k represents the index of the current time step. Timing and voltage detection are initiated, triggering an open-circuit voltage method SOC correction process every 5 minutes. When the correction process is triggered, the ampere-hour integration method calculation is paused, the open-circuit voltage of the drawer-type battery pack is measured, and the new SOC value is obtained by looking up a table, serving as the new initial value for the ampere-hour integration method. Continue performing ampere-hour integral calculations and adjust the charge / discharge efficiency based on battery temperature. The actual capacity of the battery is updated periodically through complete charge-discharge cycles. .

5. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 1, characterized in that, The BMS host control module monitors the P+ terminal voltage in real time through a voltage divider resistor network composed of pull-up resistor R1 and pull-down resistor R2, and calculates the actual voltage value according to the voltage divider principle. The voltage divider resistor network consists of pull-up resistor R1 and pull-down resistor R2. and pull-down resistors Composition, the voltage monitored by the BMS host is Then the actual voltage value The calculation formula is as follows: ; The voltage divider signal is fed into the 12-bit ADC channel of the BMS host through an RC filter circuit. The monitored P+ terminal voltage is continuously compared with the battery voltage. When the P+ terminal voltage reaches 90% of the battery voltage, the BMS host controls the relevant relays to switch states through the ULN2803 driver chip and optocoupler isolation circuit. During charging, the main relay is disconnected and the trickle charging relay is closed. During discharging, the DO2 port is triggered to light up the yellow warning light and send a status signal through the CAN bus. The BMS host communicates with external devices through the RS485 interface to obtain power demand data in real time. After analysis by the STM32F407 built-in CAN controller, the power scenario is determined.

6. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 1, characterized in that, Low-power application scenarios: The BMS host retrieves the SOC data and individual cell voltage data of each drawer-type battery pack and filters them out. >90% and voltage difference threshold For a drawer-type battery pack with a capacity of 1%, a greedy algorithm is used to prioritize battery packs with high capacity and stable voltage. Let there be a total of n battery packs. The state of charge of each battery pack is The average voltage of a single cell is Calculate the average voltage of all drawer-type battery packs. The specific calculation formula is as follows: ; in, This represents the average voltage of the drawer-type battery pack, and filters out those that meet the criteria. > And| |< The battery packs, which constitute the candidate set CAND, are used to select each candidate pack. (j Define a comprehensive evaluation value. This is used to measure its priority as a discharge combination, taking into account the historical usage count of the drawer-type battery pack. Health status The specific formula for calculating the comprehensive evaluation value is as follows: ; in, , This represents the weighting coefficient. The weights are adjusted according to actual needs to balance the impact of historical usage frequency and health status. A comprehensive evaluation value is selected from the candidate set CAND. The top 1-2 battery packs are used as the discharge combination.

7. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 1, characterized in that, High-power demand scenario: Assume there are n battery packs in total. The state of charge threshold for high-power scenarios is set as follows: >70% of those that meet the criteria were selected. > The drawer-type battery packs form a discharge assembly (DISCH). After determining the discharge assembly (DISCH), to ensure coordinated discharge of each drawer-type battery pack, the output current of each battery pack must be distributed according to a certain ratio. Let the total load current requirement be... The discharge combination set DISCH contains m battery packs, and the maximum output current capability of the k-th battery pack is: Then the current allocated to the k-th battery pack The specific calculation formula is as follows: ; The corresponding current control signal is sent to each drawer-type battery pack via the CAN bus to achieve coordinated discharge and meet the high power demand.

8. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 6, characterized in that, Based on the determined drawer-type battery pack combination decision, the BMS host sends control commands to the molded case switch, circuit breaker, and relay array. Upon receiving the command, the positive and negative relays corresponding to the target drawer-type battery pack close, connecting the target drawer-type battery pack to the charging and discharging circuit. The relays of non-target drawer-type battery packs remain open to isolate them from the charging and discharging circuit. The BMS host continuously monitors the operating status of each drawer-type battery pack, including current, voltage, and temperature parameters. If an abnormality is detected, the BMS host promptly adjusts the drawer-type battery pack combination and disconnects the faulty drawer-type battery pack to ensure the safe and stable operation of the system.

9. The photovoltaic energy storage intelligent battery pack management system based on intelligent control according to claim 1, characterized in that, The DI1 port of the protection module is connected to the digital input channel of the BMS host via a normally closed emergency stop button, with 10kΩ connected in parallel across the button. Pull-up resistors are used, and the wiring employs twisted-pair shielded cable. When the emergency stop button is pressed, the contacts open, causing the voltage at the DI1 port to rise to a high level, triggering the STM32F407's internal EXTI interrupt. The trigger time is recorded by a hardware timer, and the following circuit logic is executed immediately: The DO2 port outputs a high-level signal through the driver circuit, driving the fault indicator light and buzzer. Simultaneously, it sends an emergency stop frame to the CAN bus via a high-speed optocoupler isolation module. The CAN bus uses two-wire differential transmission, and the host side is configured with 120... Termination resistors and ESD protection devices; Each drawer-type battery pack's positive and negative relays are equipped with auxiliary normally open contacts. One end of the contact is connected to a +5V power supply, and the other end is connected to a 1kV power supply. A current-limiting resistor is connected to the BMS host DI port. When the relay is closed, the contacts are open, and the DI port level is pulled low. When the relay is open, the contacts are closed, and the DI port is maintained at a high level through a pull-up resistor. The BMS host scans the DI status through the GPIO port to simulate the I2C protocol and compares the command status with the actual status. If the relay command for a certain battery pack is open but the DI port remains at a low level, it is determined to be a contact sticking fault. The host immediately sends a second disconnect command through the hardware redundancy channel and triggers the solid-state relay to cut off the power supply circuit of the battery pack.

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