Electrical control system and method for light-weight sodium battery tray truck

Abstract

The invention relates to the technical field of tray carriers, and particularly discloses a light-weight sodium battery tray carrier electrical control system and method. The electrical control system comprises a sodium battery pack which is formed by connecting a plurality of sodium ion battery cell modules in series and is provided with a power management module; the whole vehicle control system comprises a motor controller and a multifunctional handle, and the motor controller is a wide voltage controller with the working voltage range of 12V-35V; the motor driving system comprises a walking motor and a lifting motor of which the working voltage ranges from 16V to 32V; and a vehicle-mounted charger. And the power management module of the sodium battery pack, the motor controller, the multifunctional handle and the vehicle-mounted charger are electrically connected and communicated through a CAN (Controller Area Network) bus to form a whole vehicle electrical control network. The electrical control system is composed of the sodium battery pack, the motor driving system, the whole vehicle control system and the vehicle-mounted charger, and efficient and safe operation of the vehicle is ensured through cooperative work.

Description

Technical Field

[0001] This invention relates to the field of pallet truck technology, and in particular to an electrical control system and method for a lightweight sodium battery pallet truck. Background Technology

[0002] Lightweight electric pallet trucks are widely used in warehousing and logistics. Currently, their power source mainly uses lead-acid batteries or lithium batteries.

[0003] Lead-acid batteries are inexpensive, but they have low energy density, are heavy, and their chemical properties are significantly affected by temperature. In low-temperature environments, the battery's internal resistance increases sharply, leading to a significant decrease in discharge capacity and usable capacity, which severely restricts the use of vehicles in environments such as cold storage.

[0004] Lithium-ion batteries have high energy density, but to control cost and complexity, most economical lightweight vehicle lithium-ion battery systems do not have active heating functions. This results in low charging efficiency and safety risks in low-temperature environments, and discharge performance is also limited. In addition, the raw materials for lithium-ion batteries and environmental regulations are increasingly becoming factors to consider for international market access.

[0005] Therefore, existing lightweight electric pallet trucks are inadequate in terms of their suitability for working in low-temperature environments, their ability to quickly recharge, and their environmental friendliness throughout their entire life cycle, and a new solution is urgently needed. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide an electrical control system and method for a lightweight sodium battery pallet transport vehicle powered by sodium batteries. The system comprises four components: a sodium battery pack, a motor drive system, a vehicle control system, and an on-board charger. These components work together to ensure efficient and safe operation of the vehicle.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides an electrical control system for a lightweight sodium battery pallet transport vehicle, comprising: Sodium battery packs consist of multiple sodium-ion battery cell modules connected in series and include a power management module. The vehicle control system includes a motor controller and a multi-function handle. The motor controller is a wide voltage controller with an operating voltage range of 12V to 35V. The motor drive system includes a travel motor and a hoisting motor with an operating voltage range of 16V~32V; and On-board charger; The sodium battery pack's power management module, motor controller, multi-function handle, and on-board charger are electrically connected and communicate via a CAN bus, forming the vehicle's electrical control network.

[0009] As a further improvement to the above-mentioned solution of the present invention, the sodium-ion battery module has a rated voltage of 3V, a capacity of 34AH, and a discharge cutoff voltage of 16V.

[0010] As a further improvement of the above-mentioned solution of the present invention, the sodium battery pack is also provided with a temperature sensor, a voltage sensor and a current sensor connected to the power management module. The power management module is configured to: obtain the temperature, voltage and current of the sodium battery pack according to the temperature sensor, voltage sensor and current sensor, calculate the current SOC of the sodium battery pack, and send the current SOC to the instrument in the multi-function handle for display via the CAN bus. And / or, the power management module is also configured to: monitor the static current of the electrical control system when the vehicle is in standby mode, and control the sodium battery pack to disconnect the discharge circuit after the static current has been below a set threshold for a preset time, so that the electrical control system enters a low-energy consumption state. And / or, the power management module is further configured to: estimate the current SOC of the sodium battery pack in real time, and preset a first threshold and a second threshold, wherein the first threshold is greater than the second threshold; if the current SOC is lower than the first threshold, send an undervoltage signal to the motor controller via the CAN bus; if the current SOC is lower than the second threshold, control the sodium battery pack to disconnect the discharge circuit to stop discharging.

[0011] As a further improvement to the above-described solution of the present invention, the first threshold is 10% and the second threshold is 5%.

[0012] As a further improvement to the above-mentioned solution of the present invention, the on-board charger is configured as follows: The charging control command sent by the power management module based on the temperature of the sodium battery pack is received via the CAN bus. The temperature-adaptive charging strategy is executed according to the charging control command, including: performing preparatory charging aimed at raising the cell temperature when the temperature of the sodium battery pack is less than or equal to a first preset temperature; performing reduced-current charging when the temperature of the sodium battery pack is greater than a second preset temperature; and controlling the on-board charger to enter the constant-current fast charging stage when the temperature of the sodium battery pack is greater than a third preset temperature but less than or equal to the second preset temperature, charging with the maximum safe charging current allowed at the current temperature; wherein the first preset temperature, the third preset temperature, and the second preset temperature increase sequentially, and the first preset temperature is below 0°C.

[0013] As a further improvement to the above-mentioned solution of the present invention, the first preset temperature is -20°C, the second preset temperature is 40°C, and the third preset temperature is 5°C.

[0014] As a further improvement to the above-mentioned solution of the present invention, the multi-functional handle integrates: An instrument used to display vehicle travel time, vehicle braking status, and sodium battery charge level; An accelerator used to output walking speed commands; In addition, at least one of the following operating switches: emergency reverse switch, hoisting switch, descent switch, and slow speed switch.

[0015] As a further improvement to the above-described solution of the present invention, the motor controller is configured as follows: The system receives signals from the emergency reverse switch via the CAN bus and controls the walking motor to perform emergency braking and reverse operation. The vehicle is controlled to enter an upright driving mode by receiving a signal from the simultaneous triggering of the slow switch and accelerator via the CAN bus. The system receives an undervoltage signal from the power management module via the CAN bus, controls the walking motor to enter a speed-limiting mode, and prohibits the lifting motor from operating.

[0016] This invention also provides an electrical control method for a lightweight sodium battery pallet transport vehicle, which employs the aforementioned electrical control system for a lightweight sodium battery pallet transport vehicle, and includes the following steps: Temperature-adaptive charging steps: The power management module obtains the temperature of the sodium battery pack and instructs the on-board charger to execute the corresponding charging strategy according to the temperature via the CAN bus, including preparatory charging when the temperature is below the first preset temperature, current-reducing charging when the temperature is above the second preset temperature, and constant current fast charging with the maximum safe charging current as the target between the third preset temperature and the second preset temperature; the first preset temperature, the third preset temperature, and the second preset temperature increase sequentially, and the first preset temperature is below 0°C. Collaborative discharge drive steps: During vehicle operation, in response to the operation commands issued by the multi-function handle via the CAN bus, the motor controller controls the operation of the travel motor or lifting motor. At the same time, the power management module continuously provides power to the sodium battery pack via the CAN bus. Intelligent power consumption management steps: The power management module monitors the system's static current. When it determines that the vehicle is idle, it controls the sodium battery pack to disconnect the discharge circuit to enter a low-energy consumption state.

[0017] As a further improvement to the above-described solution of the present invention, the method further includes a temperature-adaptive charging control step: The power management module monitors the temperature of the sodium battery pack in real time. Based on the temperature, a charging control command is generated and sent to the on-board charger via the CAN bus, controlling the on-board charger to execute the following strategies: If the temperature of the sodium battery pack is less than or equal to the first preset temperature, a preparatory charge aimed at raising the cell temperature is performed. If the temperature of the sodium battery pack is higher than the second preset temperature, then reduce the current charging. If the temperature of the sodium battery pack is greater than the third preset temperature but less than or equal to the second preset temperature, it will enter the constant current fast charging stage and charge at the maximum safe charging current allowed at the current temperature.

[0018] As a further improvement to the above-described solution of the present invention, in the cooperative discharge driving step: in response to the emergency reverse switch on the multi-function handle being triggered, the motor controller controls the walking motor to perform emergency braking and then reverse operation; and / or, in response to the simultaneous operation of the slow speed switch and the accelerator, the vehicle is controlled to enter the upright driving mode. And / or, the method further includes a graded undervoltage protection step: the power management module estimates the current SOC of the sodium battery pack in real time; if the current SOC is lower than a first threshold, the vehicle drive speed limit and lifting prohibition operation are triggered; if the current SOC is lower than a second threshold, the sodium battery pack is triggered to stop discharging.

[0019] As a further improvement to the above-mentioned solution of the present invention, the first preset temperature is -20°C, the second preset temperature is 40°C, and the third preset temperature is 5°C; and / or, the first threshold is 10% and the second threshold is 5%.

[0020] Compared with the prior art, the present invention has the following beneficial effects: In this invention, the multi-functional handle, motor controller, on-board charger, and sodium battery pack interact via a CAN bus. The CAN bus architecture enables multi-module collaborative control, constructing a real-time data interaction platform. Key parameters such as current, voltage, and temperature are transmitted between modules using standardized protocols, supporting millisecond-level response and dynamic strategy adjustment. This significantly improves the overall system efficiency and effectively solves the signal delay problem of traditional point-to-point connections, providing communication assurance for intelligent management of the sodium battery pack, precise motor speed regulation, and safe charging control.

[0021] This invention utilizes a sodium-ion battery pack as its power unit. Sodium-ion batteries are free of heavy metal pollution, comply with the EU RoHS directive, and offer significant advantages for export market access. The Battery Management System (BMS) achieves high-rate fast charging through intelligent charger control, supporting the sodium-ion battery pack to be fully charged within 20 minutes, unaffected by ambient temperature, significantly improving vehicle uptime. The BMS collects real-time current, voltage, and temperature data from each cell, employing a dynamic balancing algorithm to optimize energy distribution, effectively suppressing the risk of localized overheating and thus extending the battery pack's cycle life.

[0022] On the discharge side, the BMS continuously monitors the static current and reduces the system's standby power consumption through an intelligent sleep mechanism. The voltage control module implements an undervoltage protection strategy. Combined with a real-time capacity estimation algorithm, when the sodium battery capacity is 10% remaining, the controller activates the protection strategy and shuts off battery discharge when the sodium battery capacity is 5% remaining, thus avoiding deep discharge damage.

[0023] This invention addresses the wide operating voltage range of sodium battery packs by simultaneously optimizing the motor controller and motor drive scheme in the electrical control system. Through adaptive voltage matching technology, it enhances system compatibility, enabling the vehicle to maintain its green and environmentally friendly attributes while possessing core advantages such as wide temperature range adaptability, low-temperature performance stability, on-demand fast charging capability, and multiple safety protections, thus fully meeting the needs of complex operating conditions. Attached Figure Description

[0024] Figure 1 This is a block diagram of an electrical control system for a lightweight sodium battery pallet transport vehicle according to an embodiment of the present invention; Figure 2 This is a diagram showing the layout of key electrical components on a lightweight sodium battery pallet truck in an embodiment of the present invention.

[0025] Reference numerals: 1. Sodium battery pack; 1-1. Sodium-ion battery cell module; 1-2. Power management module; 1-3. Discharge relay; 2. Vehicle control system; 2-1. Motor controller; 2-2. Lifting contactor; 2-3. Multi-function handle; 2-31. Instrument; 2-32. Accelerator; 2-33. Emergency reverse switch; 2-34. Lifting switch; 2-35; 2-35. Lowering switch; 2-36. Slow speed switch; 2-4. Travel OPS switch; 2-5. Lifting lock switch; 2-6. Lowering solenoid valve; 3. Motor drive system; 3-1. Travel motor; 3-2. Lifting motor; 4. On-board charger. Detailed Implementation

[0026] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0028] Reference Figure 1 , Figure 2 This embodiment proposes an electrical control system for a lightweight sodium battery pallet transport vehicle, which includes four core components: a sodium battery pack 1, a vehicle control system 2, a motor drive system 3, and an on-board charger 4, and interacts with data through a CAN bus network.

[0029] The sodium battery pack 1 is the energy center of the entire vehicle, consisting of eight independent sodium-ion battery cell modules 1-1 connected in series. Each sodium-ion battery cell module 1-1 has a rated voltage of 3V, a capacity of 34AH, and a discharge cut-off voltage of 16V. The sodium battery pack 1 also integrates a high-performance power management module (BMS) 1-2, which integrates high-precision voltage sensors, current sensors, and temperature sensors located at key parts of the module to collect real-time voltage, current, and temperature data for each cell.

[0030] The vehicle control system 2 includes a motor controller 2-1, a lifting contactor 2-2, a multi-function handle 2-3, a lifting lock switch 2-5, and a travel OPS switch 2-4, with the motor controller 2-1 as the core. The motor controller 2-1 is designed as a wide-voltage controller, operating within a voltage range of 12-35V, controlling the travel motor 3-1 to accommodate voltage fluctuations in the sodium battery pack 1 from approximately 30V at full charge to a cutoff voltage of 16V. The multi-function handle 2-3 integrates an instrument panel 2-31, an accelerator 2-32, an emergency reverse switch 2-33, a lifting switch 2-34, a lowering switch 2-35, and a slow-speed switch 2-36. The instrument panel 2-31 receives and displays information from the BMS via the CAN bus, including battery level and vehicle operating status (when the vehicle is stationary, the instrument panel displays "P," indicating the vehicle is parked; when the vehicle is moving, the "P" disappears, indicating the vehicle is in motion). All operating commands (such as vehicle lifting, lowering, forward, backward, emergency reversal, etc.) are output by the multi-function handle 2-3 and sent to the motor controller 2-1 via the CAN bus, eliminating the traditional multi-point hard-wired connection and improving system reliability and anti-interference capability.

[0031] The motor drive system 3 includes a walking motor 3-1 and a lifting motor 3-2. The walking motor 3-1 and the lifting motor 3-2 are DC brushed motors with a power of 600-1200W and an operating voltage range of 16-32V, which can cover the fluctuation of the sodium battery from a full charge of 30V to a discharge cutoff of 16V.

[0032] The power management module BMS 1-2 is the intelligent core of battery management and has the following functions: The temperature, voltage, and current of the sodium battery pack 1 are obtained, and the charge of the sodium battery pack 1 is calculated. The charge is then sent to the instrument 2-31 inside the multi-function handle 2-3 for display via the CAN bus. When the vehicle is in standby mode, the static current of the entire electrical control system is monitored. If the static current is lower than the set threshold for a preset time, the system considers the vehicle to be idle. The BMS disconnects the discharge relays 1-3 in the sodium battery pack 1, so that the electrical control system enters a low-energy consumption state. The current SOC of sodium battery pack 1 is estimated in real time. If the current SOC is 10%, an undervoltage signal is sent to motor controller 2-1 via CAN bus to activate the protection strategy. If the current SOC is 5%, the sodium battery pack 1 is controlled to disconnect the discharge circuit to stop discharging and avoid deep discharge damage.

[0033] Motor controller 2-1 executes the corresponding control logic based on the received instructions and BMS status information: Normal walking and lifting: After the operator pulls down the multi-function handle 2-3 to close the walking OPS switch 2-4, the operator slowly moves the accelerator 2-32 in the multi-function handle 2-3 from the middle position to the limit. The walking command signal is transmitted to the motor controller 2-1 through the CAN bus. The motor controller 2-1 controls the walking motor 3-1 to adjust the speed and drive the drive axle to make the vehicle move. Press the lifting switch 2-34 in the multi-function handle 2-3 to turn it on. The system transmits the lifting command signal to the motor controller 2-1 via the CAN bus. The motor controller 2-1 controls the coil of the lifting contactor 2-2 to be energized, and the contacts of the lifting contactor 2-2 close, providing drive power to the lifting motor 3-2. The lifting motor 3-2 runs at full speed, driving the oil pump to lift the vehicle's forks. During this lifting process, the lifting locking plate moves along with the lifting contactor until it touches the lifting locking switch 2-5, turning it on. After receiving the signal from the lifting locking switch 2-5, the motor controller 2-1 disconnects the control terminal of the coil of the lifting contactor 2-2. After the lifting motor 3-2 is de-energized, the forks stop lifting. When the lowering switch 2-35 in the multi-function handle 2-3 is pressed, the lowering switch 2-35 is turned on, and the system transmits the lowering command signal to the motor controller 2-1 through the CAN bus. The motor controller 2-1 controls the lowering solenoid valve 2-6 coil to be energized, the lowering oil circuit is connected, and the fork carriage lowers.

[0034] Emergency Reverse: When the operator maneuvers the vehicle in the operator's direction, if the emergency reverse switch 2-33 on the multi-function handle 2-3 is triggered, the motor controller 2-1 receives the emergency reverse signal through the CAN bus and controls the vehicle to stop rapidly and then reverse.

[0035] Upright Operation: When the handle is in the upright position (walking OPS switch is off), press the slow speed switch 2-36 and toggle the accelerator 2-32, and the vehicle will enter the upright walking mode and run upright.

[0036] Safety linkage control: When the motor controller 2-1 receives an undervoltage signal from the BMS via the CAN bus, it immediately activates two levels of safety protection: First, it controls the travel motor 3-1 to decelerate, and the system controls the motor speed through the speed sensor in the travel motor 3-1 to control the vehicle speed; Second, it controls the winding control terminal of the lowering solenoid valve 2-4 to lose power, and the lifting motor 3-2 is de-energized, preventing the vehicle from lifting; When the sodium battery pack 1 has 5% remaining capacity, it shuts off the discharge relay 1-3, and the sodium battery pack 1 stops discharging to avoid deep discharge damage.

[0037] The on-board charger 4 communicates with the power management module BMS 1-2 via the CAN bus. The charging curve of the on-board charger 4 is provided by the BMS in the sodium battery pack 1, and it has a graded charging strategy. Low-temperature preheating stage: When the BMS detects that the temperature of the battery cell module is lower than the first preset temperature (-20℃), it determines that the battery is in a low-temperature state with high internal resistance. At this time, the BMS instructs the on-board charger 4 to enter the preparatory charging mode. The on-board charger 4 heats the battery with a small current through the heating element (such as a PI heating film) attached to the surface of the battery cell module 1-1. The heat is emitted from the heating element and heats the battery module attached to it through heat conduction, gently and safely raising the cell temperature and preventing the risk of sodium ion migration being hindered or sodium deposition caused by low temperature.

[0038] During the normal temperature fast charging phase: When the cell temperature rises to between the third preset temperature (5℃) and the second preset temperature (40℃), the BMS determines that the battery is in the high-efficiency charging temperature range. At this time, the BMS instructs the charger to enter the fast charging phase, and the on-board charger 4 performs constant current charging with the maximum safe charging current calculated by the BMS based on the real-time status and allowed, quickly replenishing the battery capacity.

[0039] High temperature protection stage: If the cell temperature rises above the second preset temperature (40°C) during charging, in order to prevent thermal runaway, the BMS will instruct the on-board charger 4 to reduce the charging current and enter the current reduction charging or constant voltage charging stage until charging is completed.

[0040] Using the above strategy, the system can replenish the battery from low to about 90% in about 20 minutes, while ensuring charging safety and efficiency across a wide temperature range.

[0041] The workflow of the electrical control system for the lightweight sodium battery pallet transport vehicle in this embodiment is as follows: When the vehicle is powered on, the BMS in the sodium battery pack 1 passes the self-test and closes the discharge relay 1-3. The motor controller 2-1 and the multi-function handle 2-3 are powered on and complete their self-tests, establish a communication network through the CAN bus, the instrument displays a ready message, and the vehicle enters standby mode.

[0042] When the operator performs operations such as walking, lifting, and lowering, the commands are transmitted via the CAN bus and executed quickly by the motor controller 2-1.

[0043] After the vehicle stops, the BMS starts static current monitoring. If it is determined to be idle, the control system enters low-energy consumption mode.

[0044] When charging is required, connect the on-board charger 4. The BMS and the on-board charger 4 communicate via the CAN bus. The BMS automatically selects and executes the above-mentioned graded charging strategy based on the real-time temperature until charging is complete.

[0045] This invention utilizes sodium batteries paired with dedicated wide-voltage devices and constructs an intelligent collaborative control system based on a CAN bus. In particular, it introduces temperature-adaptive charging management and multi-level safety protection strategies, effectively solving problems such as poor applicability of lightweight electric pallet trucks in low-temperature environments, slow charging, and range anxiety. This enables economical, efficient, safe, and environmentally friendly material handling operations.

[0046] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An electrical control system for a lightweight sodium battery pallet transport vehicle, characterized in that, include: Sodium battery pack (1), which is composed of multiple sodium-ion battery cell modules (1-1) connected in series, and is equipped with a power management module (1-2). The vehicle control system (2) includes a motor controller (2-1) and a multi-function handle (2-3). The motor controller (2-1) is a wide voltage controller with a working voltage range of 12V~35V. The motor drive system (3) includes a travel motor (3-1) and a hoisting motor (3-2) with an operating voltage range of 16V~32V; and On-board charger (4); Among them, the power management module (1-2), motor controller (2-1), multi-function handle (2-3) and on-board charger (4) of the sodium battery pack (1) are electrically connected and communicate through the CAN bus to form the vehicle electrical control network.

2. The electrical control system for the lightweight sodium battery pallet transport vehicle according to claim 1, characterized in that, The sodium-ion battery module (1-1) has a rated voltage of 3V, a voltage range of 34AH, and a discharge cutoff voltage of 16V.

3. The electrical control system of the lightweight sodium battery pallet transport vehicle according to claim 1, characterized in that, The sodium battery pack (1) is also equipped with a temperature sensor, a voltage sensor and a current sensor connected to the power management module (1-2). The power management module (1-2) is configured to: obtain the temperature, voltage and current of the sodium battery pack (1) according to the temperature sensor, voltage sensor and current sensor and calculate the current SOC of the sodium battery pack (1), and send the current SOC to the instrument (2-31) in the multi-function handle (2-3) for display via the CAN bus; And / or, the power management module (1-2) is also configured to: monitor the static current of the electrical control system when the vehicle is in standby mode, and control the sodium battery pack (1) to disconnect the discharge circuit after the static current has been below a set threshold for a preset time, so that the electrical control system enters a low-energy state. And / or, the power management module (1-2) is also configured to: estimate the current SOC of the sodium battery pack (1) in real time, and preset a first threshold and a second threshold, wherein the first preset value is greater than the second threshold; if the current SOC is lower than the first threshold, send an undervoltage signal to the motor controller (2-1) through the CAN bus; if the current SOC is lower than the second threshold, control the sodium battery pack (1) to disconnect the discharge circuit to stop discharging.

4. The electrical control system for the lightweight sodium battery pallet transport vehicle according to claim 1, characterized in that, The on-board charger (4) is configured as follows: The charging control command sent by the power management module (1-2) based on the temperature of the sodium battery pack (1) is received via the CAN bus. The temperature-adaptive charging strategy is executed according to the charging control command, including: performing preparatory charging aimed at increasing the cell temperature when the temperature of the sodium battery pack (1) is less than or equal to a first preset temperature. When the temperature of the sodium battery pack (1) is greater than the second preset temperature, it performs reduced current charging; when the temperature of the sodium battery pack (1) is greater than the third preset temperature and less than or equal to the second preset temperature, it controls the on-board charger (4) to enter the constant current fast charging stage and charges with the maximum safe charging current allowed at the current temperature; the first preset temperature, the third preset temperature, and the second preset temperature increase in sequence and the first preset temperature is lower than 0°C.

5. The electrical control system for the lightweight sodium battery pallet transport vehicle according to claim 1, characterized in that, The multi-functional handle (2-3) integrates: Instruments (2-31) for displaying vehicle travel time, vehicle braking status and the charge of sodium battery pack (1). Accelerator (2-32) used to output walking speed commands; And at least one of the following operating switches: emergency reverse switch (2-33), lifting switch (2-34), lowering switch (2-35), and slow speed switch (2-36).

6. The electrical control system for the lightweight sodium battery pallet transport vehicle according to claim 5, characterized in that, The motor controller (2-1) is configured as follows: The system receives the signal from the emergency reverse switch (2-33) via the CAN bus and controls the walking motor (3-1) to perform emergency braking and reverse operation. The vehicle is controlled to enter upright driving mode by receiving signals from the simultaneous triggering of the slow switch (2-36) and the accelerator (2-32) via the CAN bus. The system receives an undervoltage signal from the power management module (1-2) via the CAN bus, controls the walking motor (3-1) to enter a speed-limiting mode, and prohibits the lifting motor (3-2) from operating.

7. An electrical control method for a lightweight sodium battery pallet transport vehicle, characterized in that, It employs the electrical control system of the lightweight sodium battery pallet transport vehicle as described in any one of claims 1-6, and includes the following steps: Temperature adaptive charging steps: The power management module (1-2) obtains the temperature of the sodium battery pack (1) and executes the corresponding charging strategy through the CAN bus command to the on-board charger (4) according to the temperature, including preparatory charging when the temperature is lower than the first preset temperature, current reduction charging when the temperature is higher than the second preset temperature, and constant current fast charging with the maximum safe charging current as the target between the third preset temperature and the second preset temperature; the first preset temperature, the third preset temperature, and the second preset temperature increase in sequence and the first preset temperature is lower than 0℃; Collaborative discharge drive steps: During vehicle operation, in response to the operation command issued by the multi-function handle (2-3) via the CAN bus, the motor controller (2-1) controls the operation of the walking motor (3-1) or the lifting motor (3-2). At the same time, the power management module (1-2) continuously provides the sodium battery pack (1) with power via the CAN bus. Intelligent power consumption management steps: The power management module (1-2) monitors the static current of the system. When the vehicle is determined to be idle, it controls the sodium battery pack (1) to disconnect the discharge circuit to enter a low energy consumption state.

8. The control method for a lightweight sodium battery pallet transport vehicle according to claim 7, characterized in that, The method further includes a temperature-adaptive charging control step: The power management module (1-2) monitors the temperature of the sodium battery pack (1) in real time; Based on the temperature, a charging control command is generated and sent to the on-board charger (4) via the CAN bus, controlling the on-board charger (4) to execute the following strategy: If the temperature of the sodium battery pack (1) is less than or equal to the first preset temperature, a preparatory charge aimed at raising the cell temperature is performed. If the temperature of the sodium battery pack (1) is greater than the second preset temperature, then reduce the current charging; If the temperature of the sodium battery pack (1) is greater than the third preset temperature and less than or equal to the second preset temperature, it enters the constant current fast charging stage and is charged with the maximum safe charging current allowed at the current temperature.

9. The control method for a lightweight sodium battery pallet transport vehicle according to claim 7 or 8, characterized in that, In the coordinated discharge drive step: in response to the emergency reverse switch (2-33) on the multi-function handle (2-3) being triggered, the motor controller (2-1) controls the travel motor (3-1) to perform emergency braking and then reverse; and / or, in response to the simultaneous operation of the slow speed switch (2-36) and the accelerator (2-32), the vehicle is controlled to enter the upright driving mode; And / or, the method further includes a graded undervoltage protection step: the power management module (1-2) estimates the current SOC of the sodium battery pack (1) in real time; if the current SOC is lower than a first threshold, the vehicle drive speed limit and lifting prohibition operation are triggered; if the current SOC is lower than a second threshold, the sodium battery pack (1) is triggered to stop discharging.

10. The control method for a lightweight sodium battery pallet transport vehicle according to claim 9, characterized in that, The first preset temperature is -20℃, the second preset temperature is 40℃, and the third preset temperature is 5℃; and / or, the first threshold is 10% and the second threshold is 5%.

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