Braking energy recovery system of four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface inspection

Abstract

The application is suitable for a four-wheel direct-drive manned lunar electric vehicle braking energy recovery system for lunar surface inspection, comprising a reverse fuse FPGA, an electric vehicle speed measurement module for obtaining an electric vehicle speed signal, a steering handle opening measurement module for obtaining a steering handle opening signal, which are transmitted to an electric vehicle running control module and an electric vehicle braking module; the electric vehicle braking module provides a torque value to a motor drive signal module, and controls a DC brushless motor torque through a DC brushless motor drive circuit; according to the steering handle opening signal, the electric vehicle enters an electric vehicle running mode, an energy recovery mode and a braking mode; in the braking mode, the electric vehicle braking module monitors the bus voltage of the DC brushless motor drive circuit in real time, and through a bus voltage hysteresis control strategy, a current discharge resistor is dynamically started and stopped to prevent bus overvoltage damage to the circuit, and the energy recovery efficiency is maximized within a safe voltage interval. The system significantly improves the survival ability, endurance and driving safety of the lunar rover in an extreme space environment.

Description

Technical Field

[0001] This invention belongs to the field of deep space exploration and relates to a braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration. Background Technology

[0002] The four-wheel direct-drive manned lunar electric vehicle drive controller, as a torque control unit, possesses advantages such as adaptability to the lunar surface, high drive efficiency, high-power drive, fast braking, high energy recovery efficiency, and a simple and efficient system. To address the impact of high-energy particles on electronic products on the lunar surface, these products should possess resistance to single-event interference and total radiation dose interference. To cope with the complex road conditions on the lunar surface with low adhesion and to improve the reliability and safety of the electric vehicle's operation, a fast braking system is needed to ensure the astronauts' safety. Furthermore, to expand the electric vehicle's operational range on the lunar surface and improve the drive efficiency of the brushless DC motor, a simple and efficient energy recovery system is required to enhance the electric vehicle's energy utilization efficiency, ensuring that astronauts can successfully complete their designated tasks on the lunar surface. Summary of the Invention

[0003] The purpose of this invention is to provide a braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration, addressing the requirements for long range and safe driving of manned lunar electric vehicles.

[0004] To address the aforementioned technical problems, this invention provides a braking energy recovery system for a four-wheeled direct-drive manned lunar electric vehicle suitable for lunar surface exploration. The system includes an anti-fuse FPGA, which comprises an electric vehicle speed measurement module, an electric vehicle travel control module, a motor drive signal module, a control handle opening measurement module, and an electric vehicle braking module. The electric vehicle speed measurement module acquires the electric vehicle speed signal and transmits it to both the electric vehicle travel control module and the electric vehicle braking module. The control handle opening measurement module acquires the control handle opening signal and transmits it to both the electric vehicle travel control module and the electric vehicle braking module. The electric vehicle braking module provides the required torque value for the electric vehicle based on the electric vehicle speed signal and the control handle opening signal, and sends this value to the motor drive signal module. The module outputs a motor drive signal to the brushless DC motor drive circuit, which controls the torque of the brushless DC motor. When the control handle opening signal is in the range [0,1], the electric vehicle enters the driving mode. When the control handle opening signal is in the range [-0.3,0), the energy recovery mode is entered. When the control handle opening signal is in the range [-1,-0.3), the braking mode is entered. When the control handle opening signal is in the range [-1,-0.3), the electric vehicle braking module monitors the bus voltage of the brushless DC motor drive circuit in real time, activates the bus voltage hysteresis control to control the output electric vehicle braking signal, and at the same time, the motor drive signal module generates a current discharge signal to control the brushless DC motor drive circuit to prevent the circuit from burning out.

[0005] The above-mentioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, applicable to lunar surface exploration, wherein the electric vehicle travel mode is as follows: the electric vehicle travel control module monitors the electric vehicle speed signal and the control handle opening signal in real time, dynamically calculates and outputs a positive torque value to the motor drive signal module, drives four DC brushless motors, thereby driving the electric vehicle.

[0006] The above-mentioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system suitable for lunar surface exploration includes the following energy recovery mode: the electric vehicle driving control module outputs a small reverse torque value to the motor drive signal module to control the four brushless DC motors to decelerate. At the same time, due to the reverse electromotive force of the brushless DC motors, the bus voltage of the brushless DC motor drive circuit is increased. At this time, the brushless DC motors act as generators and send energy back to the battery pack.

[0007] The aforementioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, applicable to lunar surface exploration, includes the following braking mode: the electric vehicle driving control module outputs a large reverse torque value to the motor drive signal module, controlling four brushless DC motors to rapidly decelerate and brake. To address the bus voltage spike problem caused by the battery pack's inability to instantaneously absorb large currents during regenerative braking, a hysteresis comparison mechanism is introduced. When the bus voltage of the brushless DC motor drive circuit is higher than the high voltage threshold, the electric vehicle braking signal output by the electric vehicle braking module is valid. Simultaneously, the motor drive signal module outputs a current discharge signal to the brushless DC motor drive circuit, opening the discharge resistor to convert excess electrical energy into heat energy for consumption, preventing damage to the battery pack due to excessively high bus voltage. When the bus voltage is lower than the low voltage threshold, the electric vehicle braking signal output by the electric vehicle braking module is invalid, the discharge resistor is disconnected, and the system re-enters the energy recovery state, feeding electrical energy back to the battery.

[0008] The aforementioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, applicable to lunar surface exploration, includes an electric vehicle speed measurement module comprising an encoder angle sampling unit, a single wheel speed calculation unit, a wheel fault monitoring unit, and an electric vehicle speed calculation unit. The encoder angle sampling unit independently samples the encoder angle values ​​of four brushless DC motors at a fixed frequency. The single wheel speed calculation unit calculates the rotational speed of a single wheel and filters the wheel rotational speed to obtain the single wheel speed. The wheel fault monitoring unit monitors the temperature signal and power supply voltage signal of the brushless DC motors, as well as the encoder temperature signal, in real time. If the monitored values ​​are abnormal, the corresponding wheel is marked as faulty; otherwise, the corresponding wheel is marked as normal. It also identifies single wheel slippage. The electric vehicle speed calculation unit averages the speeds of the normal, non-slipping wheels to obtain the electric vehicle speed.

[0009] The above-mentioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, applicable to lunar surface exploration, wherein, for a faulty wheel, the anti-fuse FPGA releases control of the faulty wheel, causing the faulty wheel to move according to the overall vehicle driving conditions, while the electric vehicle driving control module dynamically adjusts the output torque value of the normal wheels to ensure that the output torque on the left and right sides of the vehicle is balanced.

[0010] The aforementioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, applicable to lunar surface exploration, includes a control handle opening measurement module that performs AD sampling on three redundant analog signals output by the control handle, automatically eliminating abnormal analog values, averaging the normal analog signals, and calculating the control handle opening signal. After hardware power-on reset, the control handle opening measurement module automatically completes the median value calibration of the control handle AD sampling values, and can also be calibrated subsequently via commands from ground control equipment. To avoid control handle jitter at the median value, an opening dead zone range is set.

[0011] The above-mentioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, applicable to lunar surface exploration, wherein when the control handle opening signal is in the interval [0,1], the antifuse FPGA uses a current loop to control the rotation of four DC brushless motors.

[0012] The aforementioned four-wheel direct-drive manned lunar electric vehicle braking energy recovery system, suitable for lunar surface exploration, takes into account the complex road conditions with low adhesion on the lunar surface. The anti-fuse FPGA sets preset thresholds, hysteresis control, and dead zone ranges for all vehicle control parameters to ensure the safe operation of the manned lunar electric vehicle. Simultaneously, data can be uploaded from the ground control equipment to the lunar surface control equipment for parameter modification to adapt to the complex lunar road conditions.

[0013] Compared with the prior art, the beneficial technical effects of the present invention are:

[0014] 1) Parallel data processing and real-time response based on antifuse FPGA architecture completely eliminate the risk of control instability caused by space radiation.

[0015] Existing technologies mostly use MCUs or SRAM-type FPGAs for motor control. Although they can be hardened to resist radiation through triple modular redundancy (TMR) software, they introduce large logic delays and computational jitter, making it difficult to meet the microsecond-level real-time requirements of manned lunar electric vehicles under emergency braking conditions.

[0016] By leveraging the physical characteristics of antifuse FPGAs, the risks of single-event upsets (SEU) and single-event lock-up (SEL) are eliminated at the underlying hardware level, eliminating the need for time-consuming software error correction algorithms. Simultaneously, the parallel processing logic of the antifuse FPGA allows multiple motors to independently complete sampling and calculations, enabling critical safety logic such as bus voltage hysteresis control and dynamic calculation of reverse torque values ​​to be sampled and executed within microseconds. In emergency braking situations, this system ensures absolute time determinism in the issuance and execution of braking commands, preventing program crashes or control cycle jitter caused by radiated interference, fundamentally guaranteeing the safety of manned missions.

[0017] 2) Parameter tuning for low adhesion characteristics on the lunar surface to solve the problem of braking and loss of control under soft lunar soil.

[0018] Existing anti-lock braking and traction control strategies for electric vehicles are mostly based on high adhesion coefficient calibration. When directly applied to the soft weathered layer on the lunar surface, they are very likely to cause the wheels to lock up instantly due to excessive braking torque, or even cause the entire vehicle to overturn.

[0019] This invention addresses the mechanical properties of lunar soil by specifically tuning the M / T speed measurement algorithm switching threshold, wheel slippage detection, and dynamic torque distribution. Through refined dead zone settings and hysteresis bandwidth design, the system can more sensitively detect wheel speed changes on low-traction surfaces. Combined with the driver's driving intentions, it can calculate the driving torque in a timely and accurate manner, allowing for a smooth transition between travel, energy recovery, and braking.

[0020] 3) Construct an integrated, multi-level fault-tolerant system to enhance the system's survivability under single-point failures.

[0021] By adaptively fusing the triple-redundant voting of the control handle with the M / T speed measurement algorithm for wheel speed, the system can still output high-confidence control commands even when some sensor data is affected by lunar dust interference or radiation, ensuring mission continuity and driving safety in extremely harsh space environments.

[0022] 4) Efficient bus voltage hysteresis management, balancing battery life and braking safety.

[0023] To address the issues of large variations in internal resistance and unstable charging acceptance of lithium batteries caused by extreme temperature differences on the moon, this invention designs a dual-threshold hysteresis control strategy based on real-time bus voltage. By dynamically starting and stopping the discharge resistor, when the battery cannot absorb regenerative energy (such as in a low-temperature fully charged state), it seamlessly switches to energy-consumption braking mode. This prevents overvoltage damage to power devices from the bus and avoids braking jerks caused by frequent interruptions of regenerative current, achieving smooth braking across the entire temperature range and all operating conditions. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the braking energy recovery system of a four-wheel direct-drive manned lunar electric vehicle according to an embodiment of the present invention. Detailed Implementation

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Figure 1 The diagram shown is an architecture diagram of the braking energy recovery system of a four-wheel direct-drive manned lunar electric vehicle according to an embodiment of the present invention.

[0027] like Figure 1 The braking energy recovery system of the four-wheel direct-drive manned lunar electric vehicle applicable to lunar surface exploration in this embodiment includes an anti-fuse FPGA 1. The anti-fuse FPGA 1 includes an electric vehicle speed measurement module 2, an electric vehicle travel control module 3, a motor drive signal module 4, a control handle opening measurement module 5, and an electric vehicle braking module 6.

[0028] The electric vehicle speed measurement module 2 is used to acquire the electric vehicle speed signal 7 and transmit the electric vehicle speed signal 7 to the electric vehicle travel control module 3 and the electric vehicle braking module 6 respectively.

[0029] The control handle opening measurement module 5 is used to acquire the control handle opening signal 9 and transmit the control handle opening signal 9 to the electric vehicle travel control module 3 and the electric vehicle braking module 6 respectively.

[0030] If the control handle opening signal 9 is in the range [0,1], the electric vehicle travel control module 3 monitors the electric vehicle speed signal 7 and the control handle opening signal 9 in real time, dynamically calculates and outputs the positive torque value to the motor drive signal module 4, the motor drive signal module 4 generates a motor drive signal and sends it to the DC brushless motor drive circuit 15, which drives four DC brushless motors 14 to drive the electric vehicle.

[0031] If the control handle opening signal is in the range [-0.3, 0), the energy recovery mode is entered: the electric vehicle driving control module 3 outputs a small reverse torque value to the motor drive signal module 4 according to the electric vehicle speed signal 7 and the control handle opening signal 9. The motor drive signal module 4 and the DC brushless motor drive circuit 15 control the four DC brushless motors 14 to decelerate. At the same time, due to the reverse electromotive force of the DC brushless motors 14, the bus voltage of the DC brushless motor drive circuit 15 is increased. At this time, the DC brushless motors 14 can act as generators to send energy back to the battery pack 12.

[0032] If the control handle opening signal is in the range [-1, -0.3), the braking mode is entered: the electric vehicle travel control module 3 outputs a large reverse torque value to the motor drive signal module 4 based on the electric vehicle speed signal 7 and the control handle opening signal 9. The motor drive signal module 4 and the DC brushless motor drive circuit 15 control the four DC brushless motors 14 to decelerate and brake rapidly. The electric vehicle braking module 6 monitors the bus voltage 17 of the DC brushless motor drive circuit 15 in real time, and activates the bus voltage hysteresis control to control the output electric vehicle braking signal 10. When the bus voltage 17 is higher than the high voltage threshold (high voltage... When the threshold is set to 120% of the battery pack supply voltage, the electric vehicle braking signal 10 output by the electric vehicle braking module 6 is valid. Simultaneously, the motor drive signal module 4 outputs a current discharge signal 11 to the DC brushless motor drive circuit 15, opening the discharge resistor and converting excess electrical energy into heat energy for consumption, preventing damage to the battery pack due to excessively high bus voltage. When the bus voltage 17 is lower than the low voltage threshold (set to 110% of the battery pack supply voltage), the electric vehicle braking signal 10 output by the electric vehicle braking module 6 becomes invalid, the discharge resistor is disconnected, and the system re-enters the energy recovery state, feeding electrical energy back to the battery. This strategy effectively balances braking safety and energy utilization, avoiding system oscillations caused by frequent switching.

[0033] Considering the special environment of the lunar surface, such as the effects of single-event upsets and total radiation dose, this embodiment uses an antifuse FPGA as the main processing chip. The antifuse FPGA has excellent anti-single-event upset (SEU) and anti-total radiation dose capabilities, which can effectively resist the interference of high-energy particle radiation in the deep space environment and ensure that the electronic products do not fail on the lunar surface.

[0034] It should be noted that the "smaller reverse torque value" in energy recovery mode is relative to the reverse torque value in braking mode, and the "larger reverse torque value" in braking mode is relative to the reverse torque value in energy recovery mode. In other words, the reverse torque value in braking mode is larger than that in energy recovery mode, and the reverse torque value in energy recovery mode is smaller than that in braking mode. The formula for calculating the reverse torque value is as follows:

[0035] (1)

[0036] in, This is the reverse torque value when the control handle opening signal is -1. The reverse torque value has a linear relationship with the control handle opening signal; therefore, the expected reverse torque values ​​under different control handle opening signals are:

[0037] (2)

[0038] in, This is the signal indicating the opening degree of the control handle; This represents the reverse torque value under different control handle opening signals.

[0039] According to formula (2), the control handle opening signal In the interval [-0.3, 0), the corresponding reverse torque value is... The signal is relatively small, indicating that the device is operating in energy recovery mode; the control handle opening signal is also relatively small. In the interval [-1, -0.3), the corresponding reverse torque value is... The value is relatively high, and the device is currently operating in braking mode.

[0040] Preferably, the electric vehicle speed measurement module includes an encoder angle sampling unit, a single wheel speed calculation unit, a wheel fault monitoring unit, and an electric vehicle speed calculation unit; the antifuse FPGA has parallel data processing capabilities; the encoder angle sampling unit independently samples the encoder angle values ​​of the four brushless DC motors 14 at a fixed frequency; the single wheel speed calculation unit uses the M-speed measurement algorithm (calculating the rotational speed by statistically analyzing the angle change within a fixed time window) and the T-speed measurement algorithm (calculating the rotational speed by statistically analyzing the duration of a fixed angle change value). Through hysteresis switching, when the motor speed is below a low speed threshold, it switches to the T-speed measurement algorithm; when the motor speed is above a high speed threshold (the high and low speed thresholds can be modified by uploading data from the ground control equipment to the lunar control equipment), it switches to the M-speed measurement algorithm to calculate the rotational speed of a single wheel, and then filters the wheel speed using a first-order low-pass filter to obtain the single wheel speed. The calculation formula for the first-order low-pass filter is as follows:

[0041] (3)

[0042] in, , Indicates the filter time constant. Indicates the sampling period; This indicates the wheel speed output after filtering; This indicates the wheel speed calculated in the current frame;

[0043] The wheel fault monitoring unit monitors the temperature signal, power supply voltage signal, and encoder temperature signal of each brushless DC motor in real time. If the monitored value is abnormal, the corresponding wheel is marked as faulty; otherwise, the corresponding wheel is marked as normal. When the slip ratio of a certain wheel is significantly higher than that of the other three wheels, the wheel is marked as slipping; otherwise, it is marked as not slipping. The electric vehicle speed calculation unit averages the speed of the normal, non-slipping wheels to obtain the speed of the electric vehicle. For faulty wheels, considering the unrepairability of the wheels in the lunar surface environment, the anti-fuse FPGA releases control of the faulty wheel, allowing it to move according to the overall vehicle driving conditions. At the same time, the anti-fuse FPGA dynamically adjusts the output torque value of the normal wheels to ensure that the output torque on both sides of the vehicle is balanced.

[0044] Preferably, the control handle opening measurement module 5 performs AD sampling on the three redundant analog signals output by the control handle 16, automatically removes abnormal analog signal values, and calculates the control handle opening signal by averaging the normal analog signals. After hardware power-on reset, the control handle opening measurement module 5 automatically completes the calibration of the median value of the control handle AD sampling value, and can also be calibrated by sending commands through the ground control equipment. To avoid jitter of the control handle at the median value, an opening dead zone range is set.

[0045] The logic for rejecting abnormal sampling values ​​of 3 redundant analog inputs and outputs is as follows: a voltage difference threshold is set. 0.1V:

[0046] 1) Calculate the voltage difference between the three analog signals, denoted as . , , ;

[0047] 2) If the difference between the three voltages is not greater than the threshold value Then the average value of the three analog AD sampling values ​​is taken as the output;

[0048] 3) If two of them have a voltage difference that is not greater than the threshold Then the average value of the three analog AD sampling values ​​is taken as the output;

[0049] 4) If there is only one voltage difference not greater than the threshold (Assuming) If the average of the analog AD sampling values ​​of the first and second channels is taken as the output, the analog signal of the third channel will be marked as abnormal.

[0050] 5) If the voltage difference of all three channels is greater than the threshold value. The motor is stopped, an alarm signal is output, and the ground determines which analog signal can be used.

[0051] The formula for calculating the control handle opening signal is as follows:

[0052] (4)

[0053] in, To input the control handle opening signal, i.e., to set the opening value before the dead zone, the value range is... ; The median value of the AD sampling values ​​of the control handle; The maximum positive value of the AD sampled value of the control handle; The negative maximum value of the AD sampled value of the control handle; For real-time AD sampling values ​​of the control handle;

[0054] The formula for calculating the opening dead zone setting is as follows:

[0055] (5)

[0056] in, To output the control handle opening signal, the opening value is determined by setting the opening dead zone (the dead zone range is set to ±0.05), and the value range is as follows: .

[0057] Preferably, when the control handle opening signal is in the range [0,1], the antifuse FPGA 1 uses a current loop to control the rotation of four brushless DC motors 14. The peak winding current of each brushless DC motor 14 can reach 40A, which can support two astronauts.

[0058] The braking energy recovery system of the four-wheel direct-drive manned lunar electric vehicle in this embodiment, suitable for lunar surface exploration, uses the control handle to control the opening signal to control the electric vehicle's movement, energy recovery, and braking, which greatly improves the manned lunar electric vehicle's endurance and driving safety on the lunar surface.

[0059] The four-wheel direct-drive manned lunar electric vehicle braking energy recovery system of this embodiment, suitable for lunar surface exploration, increases the safety of astronauts exploring the lunar surface and improves the energy utilization efficiency of electric vehicles.

[0060] The braking energy recovery system of the four-wheel direct-drive manned lunar electric vehicle in this embodiment, suitable for lunar surface exploration, has multi-sensor redundancy processing and wheel fault tolerance functions, which significantly improves the survivability, endurance and driving safety of the lunar rover in extreme space environments.

[0061] Obviously, those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Therefore, if these modifications and variations fall within the scope of the claims of the invention and their equivalents, the invention is also intended to include these modifications and variations.

Claims

1. A braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration, characterized in that, The system includes an antifuse FPGA, which comprises an electric vehicle speed measurement module, an electric vehicle travel control module, a motor drive signal module, a control handle opening measurement module, and an electric vehicle braking module. The antifuse FPGA, as the main control chip, has excellent resistance to single-event upset and total dose radiation, effectively resisting high-energy particle radiation interference in the deep space environment, ensuring that the control system of the manned lunar electric vehicle does not fail during the exploration mission, and greatly protecting the life safety of astronauts; the antifuse FPGA is a parallel data processing control chip, which has super real-time performance for multi-motor collaborative work, and has ultra-fast computing power and timely feedback in the face of complex road conditions with low adhesion on the lunar surface, controlling the vehicle to drive smoothly; The electric vehicle speed measurement module is used to acquire the electric vehicle speed signal and transmit the electric vehicle speed signal to the electric vehicle travel control module and the electric vehicle braking module respectively. The control handle opening measurement module is used to acquire the control handle opening signal and transmit the control handle opening signal to the electric vehicle travel control module and the electric vehicle braking module respectively; The electric vehicle braking module provides the required torque value for the electric vehicle based on the electric vehicle speed signal and the control handle opening signal, and sends it to the motor drive signal module; the motor drive signal module outputs a motor drive signal to the DC brushless motor drive circuit, which controls the DC brushless motor torque; when the control handle opening signal is in the range [0,1], the electric vehicle enters the driving mode; when the control handle opening signal is in the range [-0.3,0), the energy recovery mode is entered; when the control handle opening signal is in the range [-1,-0.3), the braking mode is entered. When the control handle opening signal is in the range [-1, -0.3), the electric vehicle braking module monitors the bus voltage of the DC brushless motor drive circuit in real time, activates the bus voltage hysteresis control to control the output electric vehicle braking signal, and at the same time, the motor drive signal module generates a current discharge signal to control the DC brushless motor drive circuit to prevent the circuit from burning out.

2. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, The electric vehicle travel mode: The electric vehicle travel control module monitors the electric vehicle speed signal and the control handle opening signal in real time, dynamically calculates and outputs the positive torque value to the motor drive signal module, drives four brushless DC motors, and thus drives the electric vehicle to travel.

3. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, The energy recovery mode: The electric vehicle driving control module outputs a small reverse torque value to the motor drive signal module to control the four brushless DC motors to decelerate. At the same time, due to the reverse electromotive force of the brushless DC motors, the bus voltage of the brushless DC motor drive circuit is increased. At this time, the brushless DC motors act as generators and send energy back to the battery pack.

4. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, The braking mode is as follows: The electric vehicle driving control module outputs a large reverse torque value to the motor drive signal module to control the four brushless DC motors to decelerate and brake rapidly. To solve the problem of bus voltage spikes caused by the battery pack's inability to absorb large currents instantaneously during regenerative braking, a hysteresis comparison mechanism is introduced: When the bus voltage of the brushless DC motor drive circuit is higher than the high voltage threshold, the electric vehicle braking signal output by the electric vehicle braking module is valid. At the same time, the motor drive signal module outputs a current discharge signal to the brushless DC motor drive circuit, opening the discharge resistor to convert excess electrical energy into heat energy for consumption, preventing the battery pack from being damaged by excessively high bus voltage. When the bus voltage is lower than the low voltage threshold, the electric vehicle braking signal output by the electric vehicle braking module is invalid, the discharge resistor is cut off, and the system re-enters the energy recovery state, feeding electrical energy back to the battery.

5. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, The electric vehicle speed measurement module includes an encoder angle sampling unit, a single wheel speed calculation unit, a wheel fault monitoring unit, and an electric vehicle speed calculation unit. The encoder angle sampling unit independently samples the encoder angle values ​​of four brushless DC motors at a fixed frequency. The single wheel speed calculation unit calculates the rotational speed of a single wheel and filters the wheel rotational speed to obtain the speed of a single wheel. The wheel fault monitoring unit monitors the temperature signal and power supply voltage signal of the brushless DC motors and the temperature signal of the encoder in real time. If the monitored value is abnormal, the corresponding wheel is marked as faulty; otherwise, the corresponding wheel is marked as normal. It also identifies the slippage state of a single wheel. The electric vehicle speed calculation unit averages the speeds of the normal, non-slipping wheels to obtain the speed of the electric vehicle.

6. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 5, characterized in that, For a faulty wheel, the anti-fuse FPGA releases control of the faulty wheel, allowing it to move according to the overall vehicle driving conditions. At the same time, the electric vehicle driving control module dynamically adjusts the output torque value of the normal wheel in real time to ensure that the output torque on both sides of the vehicle is balanced.

7. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, The control handle opening measurement module performs AD sampling on the three redundant analog signals output by the control handle, automatically removes abnormal analog values, and calculates the control handle opening signal by averaging the normal analog signals. After hardware power-on reset, the control handle opening measurement module automatically completes the median value calibration of the control handle AD sampling values, and can also be calibrated by sending commands from the ground control equipment. To avoid jitter of the control handle at the median value, an opening dead zone range is set.

8. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, When the control handle opening signal is in the range [0,1], the antifuse FPGA uses a current loop to control the rotation of four brushless DC motors.

9. The braking energy recovery system for a four-wheel direct-drive manned lunar electric vehicle suitable for lunar surface exploration as described in claim 1, characterized in that, Considering the complex road conditions on the lunar surface with low adhesion, the anti-fuse FPGA sets preset thresholds, hysteresis comparisons, and dead zones for all vehicle control parameters to ensure the safety of the manned lunar electric vehicle. At the same time, data is uploaded from the ground control equipment to the lunar control equipment to modify parameters to adapt to the complex lunar road conditions.

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