An unmanned vehicle dual-power intelligent switching method integrated with E-Fuse

Abstract

The present application relates to the technical field of power supply and safety protection of electric propulsion vehicles, and particularly relates to a double-power intelligent switching method for unmanned vehicles integrated with E-Fuse, comprising: acquiring multi-source state data of main and backup power supply channels and determining a current power supply channel; determining electromechanical equivalent impedance characteristics according to the electrical state data, and determining an electromechanical comprehensive health state; determining a corrected safety threshold according to the electromechanical comprehensive health state, E-Fuse thermal state data, power supply demand and channel carrying capacity; determining a fault type and a target control strategy according to the multi-source state data and the corrected safety threshold; and performing double-power switching and fault protection based on the target control strategy. The present application can reduce misjudgment caused by disconnection between control instructions and actual power response of the vehicle, effectively avoid access of the backup power supply to a fault load, and improve power supply reliability and fault protection capability of the electric propulsion system of the unmanned vehicle.

Description

Technical Field

[0001] This invention relates to the field of power supply and distribution and safety protection technology for electric propulsion vehicles, and in particular to a dual-power intelligent switching method for unmanned vehicles integrating E-Fuse. Background Technology

[0002] Intelligent skateboard chassis, low- and medium-speed unmanned transport vehicles, unmanned inspection vehicles, and unmanned operation vehicles typically use electric drive. To ensure the continuous operation of the autonomous driving domain controller, chassis domain controller, motor controller, drive motor, and other core electrical equipment, the unmanned vehicle electric propulsion system is usually equipped with a main power supply and a backup power supply, and is connected to the back-end common bus through two independently controllable power supply channels.

[0003] Electronic fuses (E-Fuses) integrate functions such as current detection, overcurrent protection, power supply channel switching control, fault status feedback, and recoverable protection. Compared to traditional fuses, E-Fuses can be put back into operation after a fault is cleared, making them suitable for dual power supply switching and power supply fault protection in unmanned vehicles.

[0004] Existing dual-power switching methods typically adjust the E-Fuse protection threshold based on the main power supply voltage, load current, or target current command output by the chassis controller. When the autonomous vehicle performs rapid acceleration, stationary turning, or hill climbing, the target current command and the actual channel current will increase in a short period of time. To avoid normal surge current triggering protection, existing methods typically increase the overcurrent protection threshold based on the target current command.

[0005] However, when an autonomous vehicle experiences issues such as wheels getting stuck in mud, wheels continuously slipping, drive motor mechanical stalling, or transmission mechanism jamming, the chassis controller may still continuously output large drive commands. Existing methods only increase the overcurrent protection threshold based on the target current command, without considering the actual dynamic response of the autonomous vehicle's physical entity. This can easily lead to the abnormally large current being mistaken for a normal drive demand, causing the E-Fuse to fail to disconnect the fault channel in time.

[0006] Existing dual-power switching methods are still unable to effectively distinguish between power supply side faults, load side short circuits, high line resistance, abnormal mechanical power transmission, and abnormal channel thermal conditions. When the downstream load has already experienced a short circuit, stall, or continuous slippage, if the backup power supply is directly connected to the downstream common bus, the backup power supply will still supply power to the same faulty load, failing to eliminate the fault and potentially expanding the scope of device damage.

[0007] In addition, E-Fuse, MOSFETs, wiring harnesses and connectors will accumulate heat under continuous heavy load; if a fixed current threshold is still used, it may cause the MOSFETs, connectors or wiring harnesses to overheat; if the main power channel shutdown confirmation, current decay confirmation, voltage difference judgment and pre-charge control are not available during the main and backup power switching process, cross conduction, reverse power injection and back-end common bus surge may also occur.

[0008] Therefore, there is an urgent need for an intelligent dual-power switching method for unmanned vehicles that can integrate electrical, mechanical, and thermal states and determine whether the backup power supply is allowed to take over based on the fault type. Summary of the Invention

[0009] To address the problems of existing dual-power switching methods, such as over-reliance on target control commands, inability to accurately distinguish between power-side and load-side faults, insufficient consideration of channel heat accumulation, and inadequate safety of backup power takeover, this invention provides an intelligent dual-power switching method for unmanned vehicles integrating E-Fuse, employing the following technical solution: An integrated E-Fuse intelligent dual-power switching method for unmanned vehicles includes: acquiring electrical status data of the main and backup power channels, thermal status data of electronic fuses, mechanical operating status data of the drive system, power supply demand, channel carrying capacity, and the health status of the main and backup power supplies, and determining the current power supply channel; determining the electromechanical equivalent impedance characteristics based on the electrical status data, and determining the comprehensive electromechanical health status based on the electromechanical equivalent impedance characteristics and the mechanical operating status data of the drive system; determining a corrected safety threshold based on the comprehensive electromechanical health status, the thermal status data of the electronic fuses, the power supply demand, and the channel carrying capacity of the current power supply channel; determining the fault type and target control strategy based on the electrical status data, the electromechanical equivalent impedance characteristics, the comprehensive electromechanical health status, the thermal status data of the electronic fuses, the health status of the main and backup power supplies, and the corrected safety threshold; and controlling the electronic fuses to perform backup power takeover or fault channel disconnection based on the target control strategy, and controlling the drive system to reduce output or safely shut down, thereby realizing intelligent dual-power switching and fault protection of the unmanned vehicle's electric propulsion system.

[0010] Preferably, determining the current power supply channel includes: collecting the input voltage of the main and backup power supplies, the voltage of the back-end common bus, the channel current, and the channel node temperature; obtaining the reference value of the expected bus current, the actual speed of the motor, the output torque of the motor, the actual longitudinal acceleration of the vehicle, the allowable current of each channel, and the health status of the main and backup power supplies; filtering, validating, and aligning the collected and acquired data to form the electrical status data, the thermal status data of the electronic fuse, and the mechanical operating status data of the drive system; using the reference value of the expected bus current to characterize the power supply demand; using the allowable current of each channel to characterize the channel carrying capacity; and determining the connected power supply channel as the current power supply channel.

[0011] Preferably, determining the electromechanical equivalent impedance characteristics includes: for a DC motor directly driven by a power source, when the motor current meets the detection conditions and the rate of change of current meets the quasi-steady-state conditions, determining the electromechanical equivalent impedance characteristics based on the equivalent voltage at the motor terminals, the back electromotive force determined by the actual motor speed and the back electromotive force constant, and the motor current; for a motor driven by an inverter, determining the electromechanical equivalent impedance characteristics based on the estimated winding equivalent resistance or observed stator resistance output by the motor controller; when no valid estimated or observed value is obtained, marking the electromechanical equivalent impedance characteristics as invalid, and using the electrical fault diagnosis results output by the motor controller to determine the fault type.

[0012] Preferably, determining the overall electromechanical health status includes: determining an electrical health coefficient based on the relationship between the electromechanical equivalent impedance characteristics and a preset impedance boundary; obtaining the vehicle's longitudinal actual acceleration and motor output torque from the mechanical operating status data of the drive system, compensating the vehicle's longitudinal actual acceleration for road slope and driving resistance, and projecting the compensation result onto the current drive torque direction to obtain a unidirectional equivalent longitudinal dynamic response; determining the wheel-end equivalent response torque and wheel-end equivalent drive torque based on the unidirectional equivalent longitudinal dynamic response and the motor output torque, respectively; and determining the overall electromechanical health status based on the electrical health coefficient and the degree of matching between the wheel-end equivalent response torque and the wheel-end equivalent drive torque when the vehicle is in a driving state, the motor output torque meets the detection conditions, and the electrical health coefficient is valid.

[0013] Preferably, determining the corrected safety threshold includes: determining a thermal derating factor that decreases with increasing temperature based on the channel node temperature, preset reference temperature, and preset protection shutdown temperature of the current power supply channel; determining an electromechanical health correction factor that decreases with deteriorating electromechanical health based on the overall electromechanical health status; determining a demand-side current protection boundary based on the power supply demand, current allowance, and the electromechanical health correction factor; determining the channel allowable current based on the channel carrying capacity of the current power supply channel; determining the smaller of the demand-side current protection boundary and the channel allowable current as the basic safe current boundary; and correcting the basic safe current boundary based on the thermal derating factor to obtain the corrected safety threshold.

[0014] Preferably, the determination of fault type and target control strategy includes: when the electronic fuse hardware detects a short-circuit fault, shutting down the current power supply channel; when the current of the current power supply channel continuously exceeds the corrected safety threshold, determining a continuous overload fault, and performing current limiting, derating, or channel disconnection; determining load-side electrical faults, abnormal mechanical power transmission, and channel thermal anomalies based on the electromechanical equivalent impedance characteristics, the electromechanical comprehensive health status, and the electronic fuse thermal status data; when the main power supply health status in the main and backup power supply health status indicates an abnormality, or when the main power supply channel in the main and backup power supply channels cannot continue to supply power due to the channel thermal anomaly or other channel faults, and there is no fault prohibiting takeover of the downstream load, performing a backup power supply takeover judgment; for the load-side electrical fault or the abnormal mechanical power transmission, performing fault isolation, derating, or safe shutdown, and prohibiting the connection of the backup power supply channel.

[0015] Preferably, the backup power takeover determination includes: determining whether there is a prohibited takeover fault in the back-end load based on the fault type; when the main power supply health status indicates an abnormality or the main power supply channel cannot continue to supply power, the backup power supply health status indicates a healthy state and allows charging or discharging according to the current energy flow, the back-end load does not have the prohibited takeover fault, the backup power supply channel does not have a channel fault, and the voltage difference between the backup power supply input voltage and the back-end common bus voltage meets the direct takeover conditions or the backup power supply channel has a pre-charging function or a current-limiting takeover function, determining that the backup power supply takeover conditions are met and executing the backup power supply takeover; when the backup power supply takeover conditions are not met, keeping the backup power supply channel disconnected.

[0016] Preferably, the backup power supply takeover includes: shutting down the main power channel and confirming that the main power channel has entered a shutdown state; comparing the backup power input voltage with the back-end common bus voltage after a preset dead time has elapsed and the channel current of the main power channel has decayed to a safe commutation condition; limiting reverse current injection between the main power channel and the backup power channel during switching using a reverse current blocking structure; controlling the conduction of the backup power channel when the direct takeover conditions are met, and pre-charging the back-end common bus when the direct takeover conditions are not met, and conducting the backup power channel after pre-charging is completed; stopping the takeover and keeping the backup power channel disconnected when commutation or pre-charging is not completed.

[0017] Preferably, the backup power takeover determination further includes takeover control under regenerative braking state: when the unmanned vehicle is in regenerative braking state and the main power supply health status indicates an abnormality, the backup power supply's allowed charging status, remaining backup power supply capacity, allowed backup power supply charging current, allowed reverse current of the electronic fuse, and current feedback current requirement are obtained; based on the backup power supply's allowed charging status, remaining backup power supply capacity, allowed backup power supply charging current, allowed reverse current of the electronic fuse, and current feedback current requirement, it is determined whether the backup power supply meets the feedback energy receiving conditions; if the feedback energy receiving conditions are met, the feedback current is limited and the backup power supply channel is controlled to receive feedback energy; if the feedback energy receiving conditions are not met, the regenerative braking torque is limited or stopped, and the vehicle friction braking system or energy absorption device is activated.

[0018] Preferably, the method further includes: fault latching for hardware short circuits, severe overheating, pre-charging failures, commutation timeouts, or repeated switching failures; performing a limited number of automatic retries after the instantaneous undervoltage or short-term communication anomaly disappears; re-evaluating whether the power supply channel meets the power supply recovery conditions after the power supply channel shut down due to overheating meets the temperature recovery conditions; when the main power supply health status in the main and backup power supply health status recovers from abnormal to healthy, the main power supply channel in the main and backup power supply channels meets the power supply conditions, there is no fault in the back-end load, and the unmanned vehicle operating conditions allow for back-switching, sequentially shutting down the backup power supply channel, confirming the channel current decay of the backup power supply channel, pre-charging the main power supply channel, and turning on the main power supply channel; when neither the main power supply nor the backup power supply can provide power, stopping the power switching and controlling the unmanned vehicle to limit speed, pull over, or safely shut down.

[0019] Compared with the prior art, the present invention has at least the following technical effects: This invention integrates the electrical status of the main and backup power supply channels, the thermal status of the E-Fuse, and the mechanical operating status of the drive system to determine a comprehensive electromechanical health status that reflects the electrical status of the motor and circuits and the actual power transmission status. It also combines power supply demand and channel capacity to form a modified safety threshold, which can reduce misjudgments caused by simply raising the protection threshold based on target control commands. At the same time, it determines the target control strategy based on the health status and fault type of the main and backup power supplies, which can avoid connecting the backup power supply to back-end loads with short circuits, abnormal mechanical power transmission, or other faults that prohibit takeover, thus realizing intelligent switching and fault protection of dual power supplies in the electric propulsion system of unmanned vehicles. Attached Figure Description

[0020] Figure 1 This is a flowchart of a method for intelligent switching of dual power supplies for unmanned vehicles integrating E-Fuse, according to an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and technical effects of the present invention clearer, the present invention will be described in detail below with reference to the accompanying drawings. These embodiments are used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0022] Specifically, the unmanned vehicle electric propulsion system includes a main power supply, a backup power supply, a main power supply channel, a backup power supply channel, a back-end common bus, electronic fuses, a drive system, a chassis domain controller, a motor controller, an autonomous driving domain controller, and sensor components.

[0023] The main power supply channel connects the main power supply to the back-end common bus, while the backup power supply channel connects the backup power supply to the back-end common bus. The back-end common bus provides power to the motor controller, drive motor, chassis domain controller, and core control units that require continuous power supply.

[0024] In one optional embodiment, the main and backup power supply channels are each equipped with an independent E-Fuse; in another optional embodiment, the main and backup power supply channels are integrated into an E-Fuse device with two independently controllable power supply channels; each power supply channel is equipped with current detection, channel switch control, fault status feedback and reverse current blocking functions.

[0025] like Figure 1 As shown, this embodiment executes data acquisition, state feature fusion, safety threshold correction, fault classification and control strategy execution in the order of steps S001 to S005, so that each step forms a continuous data processing and control closed loop.

[0026] S001: Obtain multi-source status data of the main and backup power supply channels and determine the current power supply channel.

[0027] Specifically, the main power supply channel is designated as Channel 1, and the backup power supply channel is designated as Channel 2, indexed by channel. Represents any power supply channel, channel index The value can be 1 or 2; based on the current power supply channel index. Indicates the current time When the main power supply channel is on, the current power supply channel index is as follows: Select 1. When the backup power channel is on, the current power supply channel index is... Take 2.

[0028] First, voltage data is acquired by sampling the main power input voltage at a frequency of 10kHz using a voltage sensor inside the E-Fuse or in the corresponding power supply channel. Backup power input voltage and the voltage of the back-end common bus All units are in volts (V); where the main power supply input voltage is... and backup power input voltage Used to determine whether the corresponding power supply is within the allowable operating range, and the voltage of the downstream common bus. Used to determine the power supply status of the back-end load and to determine the voltage difference before the backup power supply takes over.

[0029] Secondly, channel current data is acquired by sampling the main power channel current at a sampling frequency of 10kHz using current sensors in the main and backup power channels. and backup power channel current All values ​​are in amperes (A); where current power supply channel current is... Index of the current power supply channel When the main and backup power supply channels are interlocked and share the same output current sensor, the current of the current power supply channel is... The measured value is obtained using a shared output current sensor.

[0030] Furthermore, the mechanical operating status data of the drive system is acquired by using a speed sensor inside the motor controller to obtain the actual motor speed at a sampling frequency of 1kHz. The unit is r / min; when the unmanned vehicle is equipped with multiple independent drive motors, the actual speed of each drive motor is obtained separately.

[0031] The actual longitudinal acceleration of the vehicle is acquired via an inertial measurement unit (IMU) connected to the autonomous driving domain controller at a sampling frequency of 100Hz. The unit is m / s².

[0032] Obtain the motor output torque through the motor controller. The unit is N·m; for a DC motor directly driven by a power source, the motor output torque is... Based on the motor torque constant and motor current The output torque of an inverter-driven permanent magnet synchronous motor, brushless DC motor, or AC motor is obtained. The existing electromagnetic torque estimation results or actual torque observation results of the motor controller are used.

[0033] Furthermore, data characterizing power supply demand is acquired by obtaining reference values ​​for the desired bus current at an update frequency of 100Hz or higher through the chassis domain controller or motor controller. The unit is A; reference value for expected bus current. It represents the DC bus current expected to be supplied from the back-end common bus to the drive system based on the current drive demand, and serves as a characterization parameter of power supply demand.

[0034] It should be noted that the reference value for the expected bus current is... The current should be a quantity comparable to the DC current of the main and backup power supply channels; when the original output of the motor controller is a phase current command, q-axis torque current command, or electromagnetic torque command, the reference value of the desired bus current is obtained through the existing power estimation module or bus current estimation module of the motor controller. The motor phase current or q-axis torque current, which cannot be directly compared with the power supply channel current, are not directly used as the power supply demand.

[0035] Furthermore, E-Fuse thermal status data is acquired by using thermistors installed in the main and backup power channels to obtain the temperature of the main power channel node at a sampling frequency of 10Hz. and backup power channel node temperature All units are °C; when two power supply channels are integrated into the same package and share a single temperature sensor that can represent the thermal state of the two power supply channels, the same temperature measurement value is used as the node temperature of the main power supply channel. and backup power channel node temperature .

[0036] Furthermore, the health status of the primary and backup power supplies is obtained through the voltage detection circuits of the primary and backup power supplies, the battery management system (BMS), or the power management controller. and backup power health status When the voltage of the corresponding power supply is within the allowable range, charging or discharging is allowed according to the current energy flow, and there are no over-temperature, insulation, internal short circuit, communication or other power supply prohibition faults, the corresponding power supply health status value is 1; otherwise, the corresponding power supply health status value is 0.

[0037] Furthermore, data to characterize the channel carrying capacity is obtained, including the allowable current of the main power supply channel. and backup power channel allowable current The allowable current for any power supply channel is determined based on the minimum allowable current of the E-Fuse, MOSFET, wiring harness, power supply, and motor controller under the current temperature and current direction. The allowable discharge current of the corresponding power supply and power supply channel is used in the forward discharge state, and the allowable charging current of the corresponding power supply and power supply channel is used in the reverse feedback state.

[0038] Furthermore, temperature protection parameters are obtained, including the preset protection shutdown temperature of the main power channel. Backup power supply channel preset protection shutdown temperature Main power channel temperature recovery threshold and the temperature recovery threshold of the backup power channel Among them, the temperature recovery threshold of any power supply channel is lower than the preset protection shutdown temperature of the corresponding power supply channel, and the preset protection shutdown temperature is not higher than the maximum allowable operating temperature or the maximum allowable junction temperature specified in the corresponding device specifications.

[0039] Furthermore, pre-calibrated basic parameters are read, including the motor back electromotive force constant. Motor torque constant Motor winding resistance Line resistance Overall vehicle quality Wheel radius Equivalent transmission coefficient Lower limit of current detection Torque detection lower limit Electrical normal lower limit Electrical normal upper limit Severely low resistivity boundary and severely high-resistivity boundaries Among them, severely low resistivity boundary Less than the lower limit of electrical normal Electrical normal lower limit Less than the normal electrical upper limit Electrical normal upper limit Less than the severe high resistance boundary .

[0040] It should be noted that the motor winding resistance and line resistance Used for initializing or calibrating the lower limit of electrical normal operation. Electrical normal upper limit Severely low resistivity boundary and severely high-resistivity boundaries The impedance boundaries are determined by combining the motor windings, wiring harnesses, connectors, E-Fuse on-resistance, and temperature variation range through device parameters and prototype vehicle testing.

[0041] After data acquisition is completed, the acquired data is preprocessed. Hardware anti-aliasing low-pass filtering is used for the input voltage of the main and backup power supplies, the voltage of the back-end common bus, and the channel current. The filter cutoff frequency is lower than the Nyquist frequency of the corresponding sampling frequency, preferably set between 1kHz and 3kHz. Digital filtering with a time length of 5ms to 10ms is used for the actual motor speed. Digital filtering with a time length of 50ms to 100ms is used for the actual longitudinal acceleration of the vehicle and the reference value of the desired bus current. Digital filtering with a time length of 0.5s to 1s is used for the channel node temperature.

[0042] Furthermore, the collected data undergoes validity verification, which includes physical range verification, rate of change verification, timestamp verification, and communication validity verification. In the event of a single data anomaly, the previous valid value is used within a preset short-term retention period. When continuous data anomalies reach a preset number or exceed the fault tolerance time, the corresponding signal is marked as invalid, and the drive system is controlled to enter a derating state, hardware protection state, or safe shutdown state according to the importance of the signal.

[0043] Furthermore, time alignment is performed on data from different sampling frequencies, and electrical protection, mechanical condition judgment, and thermal derating are executed according to their respective update frequencies. When performing multi-source state fusion, the most recent valid low-frequency data no later than the current calculation time is read, and zero-order hold is used between adjacent update cycles.

[0044] After the above processing, the main and backup power input voltages, the back-end common bus voltage, and the channel current form electrical status data; the channel node temperature forms E-Fuse thermal status data; the actual motor speed, motor output torque, and actual vehicle longitudinal acceleration form drive system mechanical operating status data; and the bus desired current reference value... Characterizes power supply requirements; allowable current for main power supply channels and backup power channel allowable current Characterizes the channel's carrying capacity; the power supply channel that is in the conducting state among the main and backup power supply channels is determined as the current power supply channel.

[0045] S002: Determine the electromechanical equivalent impedance characteristics based on the electrical condition data, and determine the overall electromechanical health status.

[0046] First, determine the electromechanical equivalent impedance characteristics. It is a real-valued state characteristic used to characterize the equivalent resistance state formed by motor windings, lines and connection nodes, and does not represent the complete complex impedance containing reactance and phase information.

[0047] For DC motors directly driven by a power supply, when the motor current... The absolute value is not lower than the lower limit of current detection. And motor current When the rate of change is within the preset quasi-steady-state range, the electromechanical equivalent impedance characteristic is obtained according to the following formula. : ; in, For the current moment The electromechanical equivalent impedance characteristics; For the current moment The equivalent voltage at the motor terminals, in V; Let be the back electromotive force constant of the motor. The unit of the motor's actual speed The units of rotation speed used are compatible; For the current moment The actual speed of the motor; For the current moment The motor current is expressed in amperes (A).

[0048] Specifically, the equivalent voltage at the motor terminals The voltage is obtained through a motor terminal voltage detection circuit, or based on the voltage of the downstream common bus. The voltage drop of the power supply line was estimated.

[0049] For inverter-driven permanent magnet synchronous motors, brushless DC motors, or AC motors, the DC bus voltage, DC bus current, q-axis torque current, or any single phase current are not directly substituted into the aforementioned scalar formulas; the electromechanical equivalent impedance characteristics of the inverter-driven motor are also considered. It is obtained from the existing winding equivalent resistance estimate or stator resistance observation value of the motor controller.

[0050] It should be noted that when the motor controller cannot provide an effective estimate of the equivalent winding resistance or an observed stator resistance, the electromechanical equivalent impedance characteristics will be used. Marked as invalid, and use the existing short-circuit, phase loss, overcurrent, and insulation fault diagnosis results of the motor controller to participate in fault type identification; motor current The absolute value is lower than the current detection lower limit. Or motor current When the rate of change exceeds the preset quasi-steady-state range, the electromechanical equivalent impedance characteristics will be... Marked as temporarily invalid.

[0051] It should be further explained that the electromechanical equivalent impedance characteristics During the temporary invalidation period, it does not pass through a large electromechanical equivalent impedance characteristic. Directly determine if the line is open; if the busbar expected current reference value Not lower than the effective command lower limit and the back-end common bus voltage Normal, and the current power supply channel current is... Continuously below the current detection limit Then, it can be independently determined whether the circuit is open, the connector is loose, or the drive load is not connected.

[0052] Furthermore, the electrical health factor is determined based on the electromechanical equivalent impedance characteristics. With severely low resistance boundary Electrical normal lower limit Electrical normal upper limit and severely high-resistivity boundaries The relationship between the electrical health coefficients is obtained. Electrical health coefficient The value range is from 0 to 1.

[0053] Specifically, when the electromechanical equivalent impedance characteristics Located at the lower limit of electrical normal and electrical normal upper limit Between, electrical health coefficient Take 1; when the electromechanical equivalent impedance characteristic Located at a severely low resistivity boundary and electrical normal lower limit Between, electrical health coefficient Random electrical equivalent impedance characteristics Decrease and monotonically decrease; when the electromechanical equivalent impedance characteristic Located at the upper limit of normal electrical conditions and severely high-resistivity boundary Between, electrical health coefficient Random electrical equivalent impedance characteristics Increases and monotonically decreases; when the electromechanical equivalent impedance characteristics Not greater than the severe low resistance boundary or not less than the severely high-resistivity boundary At that time, electrical health coefficient Take 0.

[0054] In one alternative implementation, the electrical health factor Obtained through a preset piecewise linear mapping table; in another optional implementation, the electrical health coefficient... It is obtained by looking up a table.

[0055] Among them, electromechanical equivalent impedance characteristics Not greater than the severe low resistance boundary At that time, it was determined that there might be a serious low-resistance short circuit, a short circuit between winding turns, or a line grounding issue; electromechanical equivalent impedance characteristics Not less than the severe high-resistivity boundary At this time, it may be determined that there is a serious poor contact, loose connector, or high resistance and overheating in the circuit; mechanical stall is not directly equivalent to electromechanical equivalent impedance characteristics. When the value approaches zero, mechanical stall needs to be judged by combining the actual power response and motor output torque.

[0056] Furthermore, the equivalent longitudinal dynamic response in the same direction is determined, and the actual longitudinal acceleration of the vehicle is... Compensation is performed for road gradient, rolling resistance, air resistance, and other known driving resistances. The compensation results are then projected onto the current driving torque direction to obtain the equivalent longitudinal dynamic response in the same direction. The unit is m / s²; the dynamic response opposite to the current driving torque direction is not included in the equivalent longitudinal dynamic response in the same direction. .

[0057] When the chassis domain controller lacks vehicle dynamics observation capabilities, the equivalent longitudinal dynamic response can be obtained using a vehicle dynamics observer, slope estimator, or wheel-end drive force estimation module. .

[0058] Furthermore, the overall electromechanical health status is determined, and the wheel-end equivalent response torque is determined by the equivalent longitudinal dynamic response in the same direction. Overall vehicle quality and wheel radius The equivalent driving torque at the wheel end is determined jointly by the motor output torque. and equivalent transmission coefficient The wheel-end equivalent response torque and wheel-end equivalent drive torque are jointly determined; they are directly used to determine the degree of matching between the two.

[0059] When the motor outputs torque The absolute value is not lower than the torque detection lower limit. The driverless vehicle is in driving mode and its electrical health coefficient is [not specified]. When effective, the electromechanical comprehensive health coefficient is obtained according to the following formula. : ; in, For the current moment The electromechanical comprehensive health coefficient is used as a characterization parameter of the electromechanical comprehensive health status. For the current moment Electrical health coefficient; For the current moment The equivalent longitudinal dynamic response in the same direction; For the overall vehicle weight; The radius of the wheel; This is the equivalent transmission coefficient; For the current moment The motor output torque; This is a limiting function that restricts the calculation results to the range of 0 to 1.

[0060] Specifically, the equivalent longitudinal dynamic response in the same direction Overall vehicle quality and wheel radius The equivalent response torque at the wheel end and the equivalent transmission coefficient are generated. and motor output torque This generates an equivalent driving torque at the wheel end; both torques are measured in N·m, therefore the electromechanical comprehensive health coefficient... It is a dimensionless parameter.

[0061] It should be noted that during normal constant speed driving, the actual longitudinal acceleration of the vehicle is... Approaching zero, but equivalent longitudinal dynamic response in the same direction It includes the equivalent dynamic response to overcome road gradient, rolling resistance, and air resistance; therefore, the overall electromechanical health coefficient... The value will not approach zero simply because the autonomous vehicle is traveling at a constant speed; when the autonomous vehicle is coasting downhill, being dragged by an external force, or experiencing an impact that is not in the direction of the current driving torque, the corresponding reverse dynamic response will not be included in the equivalent longitudinal dynamic response in the same direction. This prevents the vehicle acceleration caused by external forces from being mistakenly identified as effective power transmission from the drive motor.

[0062] Specifically, the electromechanical comprehensive health coefficient A value close to 1 indicates that the electrical and power transmission conditions are normal; the overall electromechanical health coefficient... A continuous decline indicates a possible electrical abnormality, persistent wheel slippage, vehicle stuck, mechanical stall, or transmission mechanism malfunction. Abnormality confirmation is based on both duration and trend, not solely on the electromechanical comprehensive health coefficient of a single sampling period. Directly shut off the power supply channel.

[0063] Motor output torque The absolute value is lower than the torque detection lower limit. When the autonomous vehicle is in standby mode, coasting mode, or regenerative braking mode, the update of the electromechanical comprehensive health coefficient under the drive mode is suspended. It also performs standby leakage current judgment, regeneration feedback judgment, or power supply health judgment.

[0064] Furthermore, when an unmanned vehicle has multiple independent drive motors, the motor output torque, wheel-end dynamic response, and electrical status are obtained for each drive channel, and the electromechanical comprehensive health coefficient of each drive channel is obtained. When multiple drive channels are connected to the same back-end common bus, the minimum value among the multiple electromechanical comprehensive health coefficients can be used as the basis for bus-level protection judgment, and current limiting and isolation can be performed separately for the drive channel that has an abnormality.

[0065] S003: Determine the corrected safety threshold based on the overall electromechanical health status, E-Fuse thermal status data, power supply requirements, and channel capacity.

[0066] First, determine the thermal derating factor for the current power supply channel index. The thermal derating factor is obtained based on the current power supply channel node temperature, the preset reference temperature, and the current power supply channel preset protection shutdown temperature. .

[0067] Heat reduction factor Calculate according to the following formula: ; in, For the current moment The heat depreciation factor; Index of the current power supply channel The corresponding preset protection shutdown temperature; For the current moment The current temperature of the power supply channel node; Preset reference temperature; This is a limiting function that restricts the calculation results to the range of 0 to 1.

[0068] Specifically, the current power supply channel node temperature At the preset reference temperature and the current power supply channel preset protection shutdown temperature When the temperature rises, the heat depreciation factor increases. Monotonically decreasing; Current power supply channel node temperature The current power supply channel's preset protection shutdown temperature has been reached or exceeded. At that time, the temperature shutdown is directly executed, which does not only depend on the current comparison result after the safety threshold is lowered.

[0069] Secondly, determine the electromechanical health correction relationship based on the comprehensive electromechanical health coefficient. Determine the electromechanical health correction factor, which is then assigned to the overall electromechanical health coefficient. It decreases as it decreases, but is not lower than the preset minimum protection factor.

[0070] Furthermore, the demand-side current protection boundary is determined based on the reference value of the expected bus current. The current allowance and electromechanical health correction factor determine the demand-side current protection boundary. The demand-side current protection boundary decreases as the overall electrical health deteriorates, but does not decrease directly to zero due to a single anomaly.

[0071] Furthermore, the allowable current of the current power supply channel is determined based on the minimum value of the allowable current of the E-Fuse, MOSFET, wiring harness, power supply, and motor controller under the current temperature and current direction. On this basis, the smaller value between the demand-side current protection boundary and the allowable current of the current power supply channel constitutes the basic safety current boundary.

[0072] Correct safety threshold Calculate according to the following formula: ; in, For the current moment The modified safety threshold represents the maximum safe current allowed to flow through the current power supply channel, in amperes (A). For the current moment The heat depreciation factor; For the current moment The current allowable current of the current power supply channel; For the current moment Reference value for expected bus current; This is the current allowance, used to cover current control errors and sensor measurement errors; It is the minimum protection factor, and Greater than 0 and less than 1; For the current moment The overall health coefficient of electromechanical systems; It is a minimum value function.

[0073] It should be noted that the bracketed part in the formula for correcting the safety threshold is used to represent the electromechanical health correction factor and the comprehensive electromechanical health coefficient. When the value is 1, the electromechanical health correction factor is 1; the electromechanical comprehensive health coefficient As the value decreases from 1, the electromechanical health correction factor exhibits a non-linear decline; the comprehensive electromechanical health coefficient... When the value is 0, the electromechanical health correction factor is the minimum protection factor. .

[0074] It should be further explained that the revised safety threshold formula is based on the reference value of the expected bus current. Current allowable margin Together with the electromechanical health correction factor, the portion formed reflects the demand-side current protection boundary; the current allowable current of the current supply channel. This reflects the channel carrying capacity of E-Fuse, MOSFETs, wiring harnesses, power supplies, and motor controllers under the current temperature and current direction; thermal derating factor. The basic safety current boundary is further reduced based on the thermal accumulation state.

[0075] In standby mode, when the thermal derating factor When the value is greater than 0 and the current power supply channel has not triggered temperature shutdown, even if the bus desired current reference value is greater than 0, Even if it is 0, it can still be determined based on the allowable current margin. and minimum protection factor A non-zero standby current detection boundary is formed; under regenerative braking state, the current allowed current of the current power supply channel is... Use the smaller of the current power supply's allowable charging current and the E-Fuse's allowable reverse current, and then compare the actual feedback current amplitude with the corrected safety threshold. Compare them.

[0076] S004: Determine the fault type and target control strategy based on multi-source status data and corrected safety thresholds.

[0077] Specifically, fault protection includes E-Fuse hardware fast protection and controller software fusion protection.

[0078] For short-circuit faults requiring rapid disconnection, when the E-Fuse hardware comparator detects that the actual current of any conducting power supply channel exceeds the hardware short-circuit threshold, or detects desaturation of the MOSFET, abnormal voltage drop in the power supply channel, or other hardware short-circuit conditions, the hardware protection circuit directly shuts off the corresponding power supply channel. This rapid hardware protection does not wait for continuous software confirmation time, nor does it rely on electromechanical equivalent impedance characteristics. Electromechanical comprehensive health coefficient Or modify the safety threshold The calculation results.

[0079] When a hardware short circuit occurs on the back-end load side where the main power supply channel and the backup power supply channel are connected, the current power supply channel is shut off and the other power supply channel is kept disconnected to prevent the backup power supply from continuing to supply power to the same short circuit point.

[0080] In the event of a persistent overload fault, the autonomous vehicle is in drive mode, and the current power supply channel current is... The absolute value is greater than the modified safety threshold. If the overcurrent confirmation time is exceeded, a continuous overload fault is determined. The overcurrent confirmation time is calibrated through rapid acceleration, stationary turning, continuous overload, and stall tests.

[0081] For electrical faults on the load side, electromechanical equivalent impedance characteristics Not greater than the severe low resistance boundary If the low-resistance fault persists beyond the low-resistance fault confirmation time, a serious low-resistance fault is determined to exist; electromechanical equivalent impedance characteristics. Not less than the severe high-resistivity boundary If the high resistance fault continues for more than the high resistance fault confirmation time, a serious high resistance fault is determined to exist.

[0082] For abnormal mechanical power transmission, the overall electromechanical health coefficient If the temperature drops below the preset health threshold and continues to exceed the mechanical anomaly confirmation time, it is determined that there may be continuous wheel slippage, vehicle stuck, mechanical stall, or transmission mechanism abnormality. The chassis domain controller first sends a torque reduction command or current limiting command to the motor controller. If the mechanical power transmission abnormality is not eliminated within the preset handling time, the drive load channel where the abnormality occurred is shut down.

[0083] For channel thermal anomalies, the current power supply channel node temperature is at the preset reference temperature. and the current power supply channel preset protection shutdown temperature In between, through the heat depreciation factor Lower the correction safety threshold The temperature of the current power supply channel node has reached or exceeded the preset protection shutdown temperature of the current power supply channel. Immediately shut off the current power supply channel.

[0084] Furthermore, the location of the fault is classified, and the main power supply health status is assessed. The value is 1, but when a serious low-resistance fault, serious high-resistance overheating, mechanical stall, continuous slippage, or overheating of the drive load is detected, the fault will be classified as an electrical fault on the load side or an abnormal mechanical power transmission. For electrical faults on the load side or abnormal mechanical power transmission, fault load isolation, derating of the drive system output, current limiting, torque reduction, or safe shutdown will be implemented, and direct connection to the backup power channel will be prohibited.

[0085] Correspondingly, the health status of the main power supply If the value is 0, or if the main power supply channel experiences an open circuit of the MOSFET, abnormal voltage drop in the power supply channel, undervoltage of the main power supply, or other channel faults that prevent the continued supply of power, and there is no fault prohibiting the takeover of the downstream load, the fault will be classified as a power supply side fault or a power supply channel side fault, and the process will proceed to the standby power supply takeover judgment.

[0086] After completing the fault classification, the target control strategy is determined according to the fault type. Specifically, power supply side faults or power supply channel side faults correspond to backup power supply takeover judgment, continuous overload faults correspond to current limiting, drive system derating output or fault channel disconnection, load side electrical faults correspond to fault isolation or safe shutdown, abnormal mechanical power transmission corresponds to current limiting, torque reduction, drive system derating output or safe shutdown, and channel thermal abnormalities correspond to thermal derating or fault channel disconnection.

[0087] S005: Perform dual power supply switching and fault protection based on target control strategy.

[0088] First, determine whether the conditions for backup power takeover are met. Backup power takeover is only permitted if the following conditions are met simultaneously: Main power supply is in good health. The status is 0, or the main power supply channel has experienced a fault that prevents it from continuing to supply power; the backup power supply's health status... The value is 1, and the backup power supply allows charging or discharging according to the current energy flow direction; no hardware short circuit, severe low-resistance fault, or other fault that prohibits power restoration is detected in the downstream load; there are no over-temperature, over-current, MOSFET faults, or reverse blocking faults in the backup power supply channel; the backup power supply input voltage is 1. , back-end common bus voltage The voltage difference between the two meets the conditions for direct takeover, or the backup power channel has an effective pre-charging function or current-limiting takeover function.

[0089] It should be noted that if any backup power takeover condition is not met, the backup power channel should be kept disconnected, and fault isolation, derating of the drive system output, or safe shutdown should be performed according to the fault type.

[0090] When the standby power takeover conditions are met, the main power channel is shut down. The E-Fuse controller first outputs a shutdown command to the main power channel and confirms that the main power channel has entered the shutdown state through field-effect transistor drive feedback, channel status feedback or gate voltage detection.

[0091] Subsequently, the channel current decay confirmation is performed. This occurs after the minimum dead time has elapsed since the main power channel shutdown command was issued, and the main power channel current... After the current drops below the safe commutation current and remains below it for more than the commutation confirmation time, it enters the backup power supply conduction or pre-charging phase; when the main power supply channel current... If the current does not drop below the safe commutation current within the maximum commutation waiting time, the backup power supply takeover is terminated, the backup power supply channel is kept disconnected, and the commutation failure fault handling state is entered.

[0092] Furthermore, reverse current blocking is performed during the switching process, and the main and backup power supply channels are configured with reverse current blocking structures. The reverse current blocking structures adopt back-to-back field-effect transistors, ideal diode control circuits, or other circuits with reverse blocking capabilities to limit reverse current injection from the main power supply to the backup power supply and reverse current injection from the backup power supply to the main power supply.

[0093] Before the backup power channel is fully activated, a voltage difference judgment is performed to compare the backup power input voltage. With the back-end common bus voltage The voltage difference between them; when the voltage difference does not exceed the preset direct takeover threshold, the backup power supply channel is turned on according to the controlled gate slope; when the voltage difference exceeds the preset direct takeover threshold, the back-end common bus is precharged through the pre-charge branch, E-Fuse current limiting mode or controlled soft start mode.

[0094] During the pre-charging process, monitor the pre-charging current and the voltage of the downstream common bus. and the health status of backup power supply When the voltage of the back-end common bus is The preset takeover voltage range is reached, the pre-charge current is reduced to the preset allowable value, and the backup power supply is in a healthy state. When the value is 1, the backup power supply channel is fully connected; if the pre-charging is not completed within the maximum allowable pre-charging time, the pre-charging is stopped and the backup power supply channel is kept disconnected, while it is determined that there may be a short circuit in the back-end common bus, abnormal bus capacitor, or insufficient backup power supply capacity.

[0095] After the backup power channel is turned on, continue to monitor the backup power channel current. Backup power channel node temperature , back-end common bus voltage and the health status of backup power supply If an overcurrent or abnormal voltage occurs immediately after the takeover is completed, the backup power supply channel will be shut down and the system will enter fault latch-up or safe shutdown mode.

[0096] It should be noted that the switching between primary and backup power supplies adopts a dead-time switching method with disconnection before reconnection; when the core control unit requires power supply to be maintained during the switching period, a holding capacitor, supercapacitor, independent low-voltage holding power supply, or other holding power supply structure can be configured; if no holding power supply structure is configured, the switching between primary and backup power supplies is not considered a seamless switching.

[0097] Furthermore, the regenerative braking state is handled separately, provided the autonomous vehicle is in regenerative braking state and the main power supply is in good condition. When the value is 0, obtain the backup power supply's allowed charging status, remaining backup power supply capacity, allowed backup power supply charging current, allowed E-Fuse reverse current, and current feedback current requirement.

[0098] Specifically, when the backup power supply is allowed to charge, the remaining capacity of the backup power supply meets the requirements for regenerative energy storage, the allowed charging current of the backup power supply meets the current regenerative current requirement, and the allowed reverse current of the E-Fuse meets the current regenerative current requirement, it is determined that the backup power supply meets the conditions for receiving regenerative energy. When the backup power supply meets the conditions for receiving regenerative energy, the smaller value between the allowed charging current of the backup power supply and the allowed reverse current of the E-Fuse is used as the channel allowable current under regenerative braking state, and the backup power supply channel is controlled to receive regenerative energy in accordance with the main power supply channel shutdown confirmation, channel current decay confirmation, and necessary pre-charging steps.

[0099] When the backup power supply does not meet the conditions for receiving regenerative energy, the chassis domain controller sends a command to the motor controller to limit or stop the regenerative braking torque, and controls the vehicle friction braking system or energy absorption device to undertake the corresponding braking demand. The backup power supply not meeting the conditions for receiving regenerative energy includes the backup power supply not being allowed to charge, the backup power supply having insufficient remaining capacity, the backup power supply having insufficient allowable charging current, or the backup power supply having allowable charging power less than the current regenerative power. After the regenerative braking state is released, the backup power supply takeover condition judgment is re-executed.

[0100] Furthermore, fault latching and automatic retry control are implemented. When a hardware short circuit, severe overheating, pre-charging failure, commutation timeout, or repeated switching failure occurs, the corresponding fault enters the latching state and waits for manual reset or authorized recovery by the vehicle controller. For instantaneous undervoltage or short-term communication abnormality, a limited number of automatic retryes are performed after the abnormality disappears to avoid the unmanned vehicle losing its power supply capability for a long time due to instantaneous disturbances.

[0101] Furthermore, an over-temperature recovery judgment is performed. After any power supply channel is shut down due to over-temperature, the corresponding power supply channel is re-evaluated to determine whether it meets the power supply recovery conditions only if the temperature of the corresponding channel node drops below the corresponding channel temperature recovery threshold and continues to exceed the recovery confirmation time.

[0102] Furthermore, main power supply cut-off control is executed, and the main power supply is restored to a healthy state and remains stable for more than a preset time, until the main power supply input voltage... The back-off conditions are met, there are no faults in the back-end load, and the main power channel node temperature is within acceptable limits. Below the main power channel temperature recovery threshold Furthermore, when the current operating condition of the unmanned vehicle allows for a switchback, the main power supply should be switched back; specifically, this should be done by first shutting down the backup power channel and then confirming the backup power channel current. The main power switch-back is completed in the sequence of attenuation, pre-charging the main power channel, and then re-activating the main power channel.

[0103] To avoid repeated switching between the main and backup power supply channels near the critical state, a voltage hysteresis is set between the main power supply switching threshold and the main power supply cut-off threshold, and a temperature hysteresis is set between the preset protection shutdown temperature and the temperature recovery threshold.

[0104] Finally, the main power supply health status and backup power health status When both values ​​are 0, the system stops attempting to switch power, outputs a dual power supply unavailable fault message to the vehicle controller, and controls the unmanned vehicle to limit its speed, pull over, or shut down safely according to the unmanned vehicle safety policy.

[0105] In summary, through steps S001 to S005, the electrical status data of the main and backup power supply channels, the thermal status data of E-Fuse, the mechanical operating status data of the drive system, the power supply demand, the channel carrying capacity, and the health status of the main and backup power supplies form a continuous processing chain, thereby obtaining the electromechanical equivalent impedance characteristics, the electromechanical comprehensive health status, the corrected safety threshold, the fault type, and the target control strategy. Based on the target control strategy, the backup power supply takes over, the fault channel is disconnected, the drive system is derated or shut down safely, thereby realizing the intelligent switching and fault protection of the dual power supply of the unmanned vehicle electric propulsion system.

[0106] The above content is used to illustrate the technical solution of the present invention. Without departing from the concept of the present invention, those skilled in the art can calibrate or adjust the sampling frequency, confirmation time, protection boundary and recovery conditions according to the electrical architecture of the unmanned vehicle, motor type, sensor accuracy, load power and safety level. The equivalent technical solutions formed therefrom should all fall within the protection scope of the present invention.

Claims

1. A method for intelligent dual-power switching of an autonomous vehicle integrating E-Fuse, characterized in that, include: Acquire electrical status data of the main and backup power supply channels, thermal status data of electronic fuses, mechanical operating status data of the drive system, power supply demand, channel carrying capacity and health status of the main and backup power supplies, and determine the current power supply channel; The electromechanical equivalent impedance characteristics are determined based on the electrical state data, and the overall electromechanical health status is determined based on the electromechanical equivalent impedance characteristics and the mechanical operating state data of the drive system. The corrected safety threshold is determined based on the overall electromechanical health status, the thermal status data of the electronic fuse, the power supply demand, and the channel carrying capacity of the current power supply channel. Based on the electrical status data, the electromechanical equivalent impedance characteristics, the electromechanical comprehensive health status, the electronic fuse thermal status data, the main and backup power supply health status, and the corrected safety threshold, the fault type and target control strategy are determined. Based on the target control strategy, the electronic fuse is controlled to take over the backup power supply or cut off the fault channel, and the drive system is controlled to reduce output or shut down safely, so as to realize the intelligent switching of dual power supplies and fault protection of the unmanned vehicle electric propulsion system.

2. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 1, characterized in that, Determining the current power supply channel includes: The system collects the input voltage of the main and backup power supplies, the voltage of the back-end common bus, the channel current, and the channel node temperature. It also obtains the reference value of the expected bus current, the actual speed of the motor, the output torque of the motor, the actual longitudinal acceleration of the vehicle, the allowable current of each channel, and the health status of the main and backup power supplies. The collected and acquired data are filtered, validated, and time-aligned to form the electrical status data, the thermal status data of the electronic fuse, and the mechanical operating status data of the drive system. The reference value of the expected bus current is used to characterize the power supply demand, and the allowable current of each channel is used to characterize the channel carrying capacity. The connected power supply channel is then identified as the current power supply channel.

3. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 1, characterized in that, The determination of electromechanical equivalent impedance characteristics includes: For DC motors directly driven by a power supply, when the motor current meets the detection conditions and the rate of change of current meets the quasi-steady-state conditions, the electromechanical equivalent impedance characteristics are determined based on the equivalent voltage at the motor terminals, the back electromotive force determined by the actual motor speed and the back electromotive force constant, and the motor current. For inverter-driven motors, the electromechanical equivalent impedance characteristics are determined based on the estimated winding equivalent resistance or the observed stator resistance output by the motor controller. If no valid estimated or observed value is obtained, the electromechanical equivalent impedance characteristics are marked as invalid, and the electrical fault diagnosis results output by the motor controller are used to determine the fault type.

4. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 1, characterized in that, The determination of the overall electromechanical health status includes: The electrical health coefficient is determined based on the relationship between the electromechanical equivalent impedance characteristics and the preset impedance boundary; the actual longitudinal acceleration of the vehicle and the output torque of the motor are obtained from the mechanical operating status data of the drive system, and road slope and driving resistance compensation are applied to the actual longitudinal acceleration of the vehicle, and the compensation result is projected onto the current driving torque direction to obtain the equivalent longitudinal dynamic response in the same direction; the equivalent longitudinal dynamic response in the same direction and the output torque of the motor are determined based on the equivalent response torque at the wheel end and the equivalent driving torque at the wheel end, respectively; when the vehicle is in driving state, the output torque of the motor meets the detection conditions, and the electrical health coefficient is valid, the comprehensive electromechanical health status is determined based on the electrical health coefficient and the degree of matching between the equivalent response torque at the wheel end and the equivalent driving torque at the wheel end.

5. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 1, characterized in that, The determination of the corrected security threshold includes: A thermal derating factor that decreases with increasing temperature is determined based on the current power supply channel node temperature, preset reference temperature, and preset protection shutdown temperature; an electromechanical health correction factor that decreases with deteriorating electromechanical health status is determined based on the overall electromechanical health status; a demand-side current protection boundary is determined based on the power supply demand, current allowance, and the electromechanical health correction factor; a channel allowable current is determined based on the current power supply channel's channel carrying capacity; the smaller of the demand-side current protection boundary and the channel allowable current is determined as the basic safe current boundary, and the basic safe current boundary is corrected based on the thermal derating factor to obtain the corrected safe threshold.

6. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 1, characterized in that, The determination of the fault type and target control strategy includes: When the electronic fuse hardware detects a short-circuit fault, it shuts down the current power supply channel. When the current in the current power supply channel continuously exceeds the corrected safety threshold, a continuous overload fault is identified, and current limiting, derating, or channel disconnection is performed. Based on the electromechanical equivalent impedance characteristics, the electromechanical comprehensive health status, and the electronic fuse thermal status data, load-side electrical faults, abnormal mechanical power transmission, and channel thermal anomalies are identified. When the main power supply health status in the main and backup power supply health status indicates an abnormality, or when the main power supply channel in the main and backup power supply channels cannot continue to supply power due to the channel thermal anomaly or other channel faults, and there is no fault prohibiting takeover of the downstream load, a backup power takeover judgment is performed. For the load-side electrical fault or the abnormal mechanical power transmission, fault isolation, derating, or safe shutdown are performed, and the backup power supply channel is prohibited from being connected.

7. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 6, characterized in that, The backup power takeover determination includes: Based on the fault type, determine whether there is a prohibited takeover fault in the back-end load; when the main power supply health status indicates an abnormality or the main power supply channel cannot continue to supply power, the backup power supply health status indicates a healthy state and allows charging or discharging according to the current energy flow, the back-end load does not have the prohibited takeover fault, the backup power supply channel does not have a channel fault, and the voltage difference between the backup power supply input voltage and the back-end common bus voltage meets the direct takeover conditions or the backup power supply channel has a pre-charging function or a current-limiting takeover function, determine that the backup power supply takeover conditions are met and execute the backup power supply takeover; if the backup power supply takeover conditions are not met, keep the backup power supply channel disconnected.

8. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 7, characterized in that, The backup power supply connection includes: The main power channel is shut down and confirmed to be in the shutdown state. After a preset dead time has elapsed and the channel current of the main power channel has decayed to a safe commutation condition, the backup power input voltage is compared with the back-end common bus voltage. During the switching process, a reverse current blocking structure is used to limit reverse current injection between the main power channel and the backup power channel. When the direct takeover condition is met, the backup power channel is controlled to be turned on. When the direct takeover condition is not met, the back-end common bus is pre-charged, and the backup power channel is turned on after the pre-charging is completed. If the commutation or pre-charging is not completed, the takeover is stopped and the backup power channel is kept disconnected.

9. A method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 7, characterized in that, The backup power takeover determination also includes takeover control under regenerative braking conditions: When the autonomous vehicle is in regenerative braking mode and the main power supply health status indicates an abnormality, the backup power supply's allowed charging status, remaining backup power supply capacity, allowed backup power supply charging current, allowed reverse current of the electronic fuse, and current feedback current requirement are obtained; based on the backup power supply's allowed charging status, remaining backup power supply capacity, allowed backup power supply charging current, allowed reverse current of the electronic fuse, and current feedback current requirement, it is determined whether the backup power supply meets the feedback energy receiving conditions; When the feedback energy receiving conditions are met, the feedback current is limited and the backup power channel is controlled to receive feedback energy; when the feedback energy receiving conditions are not met, the regenerative braking torque is limited or stopped, and the vehicle friction braking system or energy absorption device is activated.

10. The method for intelligent dual-power switching of an unmanned vehicle integrating E-Fuse according to claim 1, characterized in that, Also includes: Fault latching is performed for hardware short circuits, severe overheating, pre-charging failures, commutation timeouts, or repeated switching failures; a limited number of automatic retries are performed after the instantaneous undervoltage or short-term communication anomalies disappear; after the power supply channel shut down due to overheating meets the temperature recovery conditions, the power supply channel is reassessed to determine whether it meets the power supply recovery conditions; when the main power supply health status in the main and backup power supply health status recovers from abnormal to healthy, the main power supply channel in the main and backup power supply channels meets the power supply conditions, there is no fault in the back-end load, and the unmanned vehicle's operating conditions allow for back-switching, the backup power supply channel is shut down sequentially, the channel current decay of the backup power supply channel is confirmed, the main power supply channel is pre-charged, and the main power supply channel is turned on; when neither the main power supply nor the backup power supply can provide power, power switching is stopped, and the unmanned vehicle is controlled to limit speed, pull over, or safely shut down.

Images