A self-starting charging method and system for a range extended vehicle

Abstract

The application relates to the technical field of intelligent automobiles and discloses a self-starting charging method and system for a range-extender automobile, the method comprising the following steps: when the vehicle is in an off state and receives an intermittent power supply command opening signal, the state of the battery and the external environment is monitored, the vehicle controller is woken up when the basic charging permission condition is met, the battery state parameters, environmental information and vehicle state parameters are collected, and a preset range extender efficiency MAP and an environmental noise constraint table are loaded; a battery state of charge (SOC) evaluation method based on fuzzy logic is introduced; low, medium and high power demand intervals and their trapezoidal membership functions are defined; an accurate SOC value is converted into the membership degree of various charging demand levels; the fine and stepless evaluation of the battery power demand is realized; the method overcomes the limitations of the traditional fixed threshold criterion and can more accurately identify the real demand of the battery in the boundary state.

Description

Technical Field

[0001] This invention relates to the field of intelligent vehicle technology, specifically to a self-starting charging method and system for range-extended electric vehicles. Background Technology

[0002] A range-extended electric vehicle is an electric vehicle equipped with an onboard auxiliary power generation system, consisting of an engine, generator, and controller. When the onboard rechargeable energy storage system cannot meet the vehicle's range requirements, the range extender provides electrical energy to the vehicle's power system.

[0003] Currently, due to the unpredictability of battery power consumption in range-extended electric vehicles when the engine is off and the complexity of usage scenarios, the battery status information used to make autonomous charging decisions is relatively limited. It is usually based on fixed thresholds and cannot accurately assess the battery's power demand range. When the battery is at the boundary of its charge level, it will cause charging requests to be too frequent and untimely, which will affect the user experience and accelerate battery aging.

[0004] Therefore, a self-starting charging method and system for range-extended electric vehicles is proposed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a self-starting charging method and system for range-extended electric vehicles, solving the problem mentioned in the background art of the inability to accurately assess the battery's power demand range.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a self-starting charging method and system for range-extended electric vehicles, the method comprising the following steps: S1. When the vehicle is in a powered-off state and receives an intermittent charging command start signal, perform battery status and external environment status monitoring, and wake up the vehicle controller when the basic charging permission conditions are met. S2. Collect battery status parameters, environmental information and vehicle status parameters, and load the preset range extender efficiency MAP and environmental noise constraint table. S3. Evaluate the collected battery state of charge (SOC) value based on fuzzy logic, and calculate the membership degree of the SOC value to the low power demand range, medium power demand range, and high power demand range. S4. Calculate the target power generation based on the membership degree weighting, determine the final power generation in combination with the battery physical constraints, and take the optimal fuel economy, minimum operating noise and best following of the final power generation of the range extender as the comprehensive optimization objectives. Perform multi-objective optimization within the constraints of the range extender efficiency MAP to generate the optimal speed and optimal torque. S5. Perform a safety review of the optimal speed and the optimal torque based on the safety rule decision tree, and generate a reviewed speed control command and torque control command. S6. Send the speed control command and the torque control command to the range extender controller to control the range extender to start and run at the corresponding optimal speed operating point to charge the power battery. S7. During the charging process, S2 to S6 are repeated at fixed intervals to dynamically update the optimal speed and the optimal torque; S8. When the battery status parameters, vehicle status parameters, and environmental information do not meet the basic charging permit conditions and safety rules, control the range extender to shut down and end the charging process.

[0007] Preferably, step S1 includes the following steps: S11. The battery management system wakes up automatically based on an internal clock and a preset cycle, and continuously monitors the voltage, temperature and internal resistance signals of the power battery. S12. When the state of charge (SOC) value of the power battery is detected to be lower than the preset wake-up threshold, the battery management system sends a wake-up request message to the vehicle controller via the CAN bus. S13. After the vehicle controller is woken up, it reads the vehicle speed signal, remaining fuel signal, battery temperature signal, in-vehicle occupant monitoring signal, and the status of the intermittent charging command. S14. When the following conditions are met simultaneously, a basic charging permission signal is generated: the intermittent charging command is in the on state, the vehicle speed is zero, the remaining fuel is greater than the first fuel threshold, the battery temperature is within the preset operating temperature range, and there is no one in the vehicle.

[0008] Preferably, step S2 includes the following steps: S21. Obtain the current battery SOC value, battery temperature, battery internal resistance and battery open circuit voltage from the battery management system; S22. Obtain occupant monitoring signals, vehicle GPS location information, and range extender coolant temperature from environmental sensors and body controller; S23. Obtain vehicle remaining fuel information from the CAN bus; S24. Retrieve the range extender efficiency MAP from the memory of the vehicle controller. The range extender efficiency MAP is a data mapping table characterizing the fuel consumption rate of the range extender under different speed and torque conditions. S25. Retrieve the environmental noise constraint table from the memory of the vehicle controller. The environmental noise constraint table defines the maximum operating noise level of the range extender allowed in different geographical locations.

[0009] Preferably, step S3 includes the following steps: S31. Define fuzzy power demand intervals for SOC values, including low power demand intervals, medium power demand intervals, and high power demand intervals. Each interval is described using a trapezoidal membership function. Among them, the trapezoidal parameters of the low power demand range for Its membership function is: ; Trapezoidal parameters of the medium power demand range for Its membership function is: ; Trapezoidal parameters of the high power demand range for Its membership function is: ; S32. Substitute the current battery SOC value into the trapezoidal membership function to calculate its membership degree values ​​for low, medium, and high power demand ranges, respectively. , and .

[0010] Preferably, step S4 includes the following steps: S41, Based on the membership degree , and Weighted calculations were performed to obtain the preliminary target power generation. The calculation formula is: ; in, , , Preset rated power generation corresponding to high, medium and low charging demand levels respectively; S42. Calculate the maximum acceptable charging power of the current power battery based on the battery open-circuit voltage and the battery internal resistance. ; S43. Compare the preliminary target power generation. With the maximum acceptable charging power The smaller value among them is determined as the final power generation. ; S44, Construct a system based on the range extender speed and output torque For multi-objective optimization functions of decision variables: ; in, For comprehensive scoring, , , These are the weight coefficients obtained through training with historical data. The preferred rotational speed is obtained by querying the environmental noise constraint table using the vehicle's GPS location information. This refers to the final power generation capacity. S45. Under the conditions of satisfying the specified speed range, torque range, estimated operating noise not exceeding the maximum operating noise level, and actual power generation not less than 0.8 times the final power generation. Under the constraints, the discrete operating points in the range extender efficiency MAP are traversed, and the comprehensive score for each feasible point is calculated. ; S46. Select the comprehensive score The minimum operating point is used to output the optimal speed and torque.

[0011] Preferably, step S5 includes the following steps: S51. Establish an independent security decision tree, which contains multiple layers of decision nodes; S52. Input the optimal speed, the optimal torque, the real-time collected vehicle status parameters and environmental information into the safety decision tree; S53. The safety decision tree executes judgments in sequence: when the smart key is detected inside the vehicle and the vehicle occupant monitoring signal indicates that someone is inside, the range extender stop command is output; when the battery temperature is detected to exceed the first safety threshold, the power reduction operation mode is triggered, and the optimal speed and optimal torque after power reduction are recalculated; when the remaining fuel level of the vehicle is detected to be lower than the second fuel level threshold, the range extender stop command is output. S54. When all safety judgment nodes are passed, the speed control command and the torque control command containing the optimal speed and the optimal torque are generated. When any safety rule is triggered, the corresponding safety control command is generated.

[0012] Preferably, step S6 includes the following steps: S61. The vehicle controller encapsulates the speed control command and the torque control command into a torque request message in speed mode and sends it to the range extender controller via the CAN bus. S62. The range extender controller controls the generator to operate as a motor, powered by the power battery to drive the engine to a preset ignition speed; S63. When the engine reaches the preset ignition speed, the range extender controller sends an ignition enable signal to the engine controller to control the engine fuel injection and ignition. S64. After the engine is successfully ignited, the range extender controller switches to speed mode, controls the generator to be driven by the engine, and outputs electrical energy through the inverter according to the operating point corresponding to the optimal speed and the optimal torque to charge the power battery.

[0013] Preferably, in step S7, the fixed-period repetitive execution process further includes the following steps: S71. During each cycle execution, based on the latest collected vehicle GPS location information, dynamically update the environmental preference speed queried in the environmental noise constraint table. ; S72. Calculate the speed change rate based on the optimal speed calculated in the latest cycle and the actual operating speed in the previous cycle. When the speed change rate exceeds a preset threshold, perform smoothing filtering on the optimal speed before sending it out.

[0014] Preferably, step S8 includes the following steps: S81. Throughout the entire charging cycle, continuously monitor the battery status parameters, vehicle status parameters, and environmental information; S82. When any of the following conditions are monitored, a charging termination signal is generated: the intermittent charging command is manually turned off, the vehicle speed is not zero, the remaining fuel level of the vehicle is lower than the third fuel level threshold, the battery temperature exceeds the preset operating temperature range, someone is detected in the vehicle, and the smart key is detected. S83. Based on the charging termination signal, the vehicle controller sends a shutdown command to the range extender controller to shut down the range extender and sequentially power down the high-voltage system and the low-voltage system, so that the vehicle returns to a dormant state.

[0015] Preferably, the system includes: The status monitoring and permission judgment module periodically monitors the status of the power battery through the battery management unit, and wakes up the system when the battery state of charge is lower than the threshold. The system generates a basic charging permission signal by combining the vehicle speed, fuel level, presence of personnel and intermittent charging commands through the environment and vehicle status verification unit. The multimodal data acquisition module receives the basic charging permission signal, obtains the real-time battery status through the battery parameter acquisition unit, reads the vehicle status and environmental information through the vehicle bus interface unit, and calls the pre-stored range extender efficiency MAP and environmental noise constraint table through the model loading unit. The SOC state fuzzy evaluation module, based on the SOC value in the real-time battery state, sets the trapezoidal membership function of low, medium and high power demand intervals through the fuzzy interval definition unit, and outputs the membership degree of the current SOC to each power demand interval through the membership degree calculation unit. The multi-objective optimization decision module receives the membership degree, determines the final power generation by combining the target power calculation unit with the battery physical constraints, and constructs a comprehensive scoring function in the optimization solution unit based on fuel economy, noise and power following performance, and iterates through the range extender efficiency MAP to solve for the optimal speed and optimal torque. The safety rule fusion and instruction generation module receives the optimal speed and optimal torque, performs multi-level condition verification through the safety decision tree unit, and generates speed and torque control instructions and safety intervention instructions by the control instruction encapsulation unit. The dynamic adjustment and monitoring module periodically triggers the multimodal data acquisition module to re-execute the safety rule fusion and instruction generation module during the charging process. It dynamically adjusts the operating point through the operating point update unit and outputs a charging termination signal through the termination condition judgment unit when the condition is not met, thereby controlling the range extender to shut down.

[0016] Compared with the prior art, the present invention provides a self-starting charging method and system for range-extended electric vehicles, which has the following beneficial effects: 1. In this invention, when making the self-starting charging decision of the range extender, a battery state of charge (SOC) evaluation method based on fuzzy logic is introduced. Low, medium, and high power demand ranges and their trapezoidal membership functions are defined, and the accurate SOC value is transformed into a membership degree for multiple charging demand levels. This achieves a refined and stepless evaluation of battery power demand. This method overcomes the limitations of traditional fixed threshold criteria, can more accurately identify the battery's real demand in boundary states, and reduces unnecessary frequent starts and charging delays. This not only optimizes the user experience but also helps to extend the service life of the power battery.

[0017] 2. In this invention, when planning charging power and range extender operating point, a comprehensive scoring function is constructed with the objectives of optimal fuel economy, minimum operating noise, and optimal follow-up to target power generation. Within the constraints of the range extender efficiency MAP, multi-objective optimization is performed to generate the optimal speed and optimal torque. This method achieves dynamic trade-offs and synergistic optimization among multiple key performance indicators such as fuel consumption, noise control, and charging demand response, ensuring that the optimal power generation condition can be selected in different scenarios, thereby improving the system's environmental adaptability and overall energy efficiency.

[0018] 3. In this invention, during the entire self-starting charging process, an independent safety rule decision tree is established to perform multi-layer safety verification of control commands. The entire process from data acquisition to command generation is repeatedly executed at fixed intervals, realizing continuous monitoring and dynamic response of battery status, vehicle status, and environmental information. This closed-loop dynamic control framework ensures that the system can respond to various changes and potential risks in real time and safely terminate charging when conditions are not met. This enhances the safety and reliability of the automatic charging process of range-extended vehicles in unattended mode, prevents safety risks, and ensures the robust operation of the system. Attached Figure Description

[0019] Figure 1 This is a flowchart of a self-starting charging method for a range-extended electric vehicle according to the present invention; Figure 2 This is a schematic diagram of the self-starting charging system for a range-extended electric vehicle according to the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figure 1 - Figure 2 The self-starting charging method and system for a range-extended electric vehicle includes the following steps: S1. When the vehicle is in a powered-off state and receives an intermittent charging command start signal, perform battery status and external environment status monitoring, and wake up the vehicle controller when the basic charging permission conditions are met. S2. Collect battery status parameters, environmental information and vehicle status parameters, and load the preset range extender efficiency MAP and environmental noise constraint table. S3. Evaluate the collected battery state of charge (SOC) value based on fuzzy logic, and calculate the membership degree of the SOC value to the low power demand range, medium power demand range, and high power demand range. S4. Calculate the target power generation based on membership weights, determine the final power generation based on battery physical constraints, and take the optimal fuel economy, minimum operating noise, and best tracking of the final power generation of the range extender as comprehensive optimization objectives. Perform multi-objective optimization within the constraints of the range extender efficiency MAP to generate the optimal speed and optimal torque. S5. Based on the safety rule decision tree, perform a safety review of the optimal speed and optimal torque, and generate the reviewed speed control command and torque control command. S6. Send the speed control command and torque control command to the range extender controller to control the range extender to start and run at the corresponding optimal speed operating point to charge the power battery. S7. During the charging process, S2 to S6 are repeated at fixed intervals to dynamically update the optimal speed and optimal torque. S8. When the battery status parameters, vehicle status parameters, and environmental information do not meet the basic charging permit conditions and safety rules, control the range extender to shut down and end the charging process.

[0022] S1 includes the following steps: S11. The battery management system wakes up automatically based on an internal clock and a preset cycle, and continuously monitors the voltage, temperature and internal resistance signals of the power battery. S12. When the state of charge (SOC) value of the power battery is detected to be lower than the preset wake-up threshold, the battery management system sends a wake-up request message to the vehicle controller via the CAN bus. S13. After the vehicle controller is woken up, it reads the vehicle speed signal, remaining fuel signal, battery temperature signal, in-vehicle occupant monitoring signal, and the status of intermittent power replenishment command. S14. When the following conditions are met simultaneously, a basic charging permission signal is generated: the intermittent charging command is enabled, the vehicle speed is zero, the remaining fuel is greater than the first fuel threshold, the battery temperature is within the preset operating temperature range, and there is no one in the vehicle.

[0023] S2 includes the following steps: S21. Obtain the current battery SOC value, battery temperature, battery internal resistance, and battery open-circuit voltage from the battery management system; S22. Obtain occupant monitoring signals, vehicle GPS location information, and range extender coolant temperature from environmental sensors and body controller; S23. Obtain vehicle remaining fuel information from the CAN bus; S24. Retrieve the range extender efficiency MAP from the vehicle controller's memory. The range extender efficiency MAP is a data mapping table that characterizes the fuel consumption rate of the range extender under different speed and torque conditions. The range extender efficiency MAP is a two-dimensional lookup table with the row index being the engine speed, the column index being the output torque, and the table content being the fuel consumption rate under the corresponding conditions. S25. Retrieve the environmental noise constraint table from the vehicle controller's memory. The environmental noise constraint table defines the maximum allowable operating noise level of the range extender for different geographical locations. The environmental noise constraint table is a mapping table between geographical locations and the maximum allowable noise level. The system obtains rough geographical location information through the vehicle's GPS and combines it with onboard time information to query this table to obtain the environmental preference speed for the current scenario. The corresponding maximum permissible noise level.

[0024] S3 includes the following steps: S31. Define fuzzy power demand intervals for SOC values, including low power demand intervals, medium power demand intervals, and high power demand intervals. Each interval is described using a trapezoidal membership function. Among them, the trapezoidal parameters in the low power demand range for Its membership function is: ; Trapezoidal parameters for medium-sized electricity demand range for Its membership function is: ; Trapezoidal parameters in high power demand range for Its membership function is: ; S32. Substitute the current battery SOC value into the trapezoidal membership function to calculate its membership degree for low, medium, and high power demand ranges respectively. , and .

[0025] S4 includes the following steps: S41, Based on membership degree , and Weighted calculations were performed to obtain the preliminary target power generation. The calculation formula is: ; in, , , Preset rated power generation capacity corresponding to high, medium and low charging demand levels respectively; S42. Calculate the maximum acceptable charging power of the current power battery based on the battery open-circuit voltage and battery internal resistance. ; S43. Compare the preliminary target power generation capacity. With maximum acceptable charging power The smaller value among them is determined as the final power generation. ; S44, Construct a system based on the range extender speed and output torque For multi-objective optimization functions of decision variables: ; in, For comprehensive scoring, , , These are the weight coefficients obtained through training with historical data. The preferred rotational speed is obtained by querying the environmental noise constraint table based on the vehicle's GPS location information. This refers to the final power generation capacity. S45. Under the conditions of meeting the speed range, torque range, estimated operating noise not exceeding the maximum operating noise level, and actual power generation not less than 0.8 times the final power generation. Under the constraints, traverse the discrete operating points in the range extender efficiency MAP and calculate the comprehensive score for each feasible point. ; S46. Select the comprehensive score The minimum operating point is used to output the optimal speed and torque.

[0026] S5 includes the following steps: S51. Establish an independent security decision tree, which contains multiple layers of decision nodes; S52. Input the optimal speed, optimal torque, real-time collected vehicle status parameters and environmental information into the safety decision tree; S53, Security decision tree executes judgments sequentially: When the smart key is detected inside the vehicle and the occupant detection signal indicates that someone is inside the vehicle, a range extender stop command is output. When battery temperature is detected Exceeding the first safety threshold When this happens, the power reduction operation mode is triggered, and the optimal speed and optimal torque after power reduction are recalculated; Among them, the first security threshold Calculated dynamically using the following formula: ; Formula explanation: The first safety threshold, This refers to the reference safe temperature corresponding to the battery chemistry system. This is the ambient temperature compensation coefficient. Real-time ambient temperature; This formula shows that the safety threshold is not a fixed value; it varies with the ambient temperature. As the temperature rises, the battery's heat dissipation becomes worse, therefore the safety upper limit is... It should be dynamically reduced to reserve a greater safety margin and achieve preventative protection; When the vehicle's remaining fuel level is detected When the oil level is below the second oil level threshold If so, the range extender will stop command will be output; Among them, the second oil quantity threshold Defined by the following formula: ; Formula explanation: This is the second oil quantity threshold. To ensure the absolute minimum safe oil level, This is a proportionality coefficient representing the total capacity of the fuel tank. This refers to the total capacity of the vehicle's fuel tank. This formula guarantees a safety threshold. It is the absolute minimum fuel quantity and a certain proportion of the total capacity The larger of the two values ​​takes into account the common mechanical protection needs of all vehicle models, and is adaptively adjusted according to the fuel tank size of specific vehicles, making the rules more universal and reasonable. S54. When all safety judgment nodes are passed, a speed control command and a torque control command containing the optimal speed and the optimal torque are generated. When any safety rule is triggered, a corresponding safety control command is generated.

[0027] S6 includes the following steps: S61. The vehicle controller encapsulates the speed control command and torque control command into a torque request message in speed mode and sends it to the range extender controller via the CAN bus. S62, The range extender controller controls the generator to operate as an electric motor, powered by the power battery to drive the engine to the preset ignition speed; S63. When the engine reaches the preset ignition speed, the range extender controller sends an ignition enable signal to the engine controller to control the engine fuel injection and ignition. S64. After the engine is successfully ignited, the range extender controller switches to speed mode, controls the generator to be driven by the engine, and outputs electrical energy through the inverter according to the operating point corresponding to the optimal speed and optimal torque to charge the power battery.

[0028] In S7, the repetitive execution process with a fixed period also includes the following steps: S71. During each cycle execution, dynamically update the environmental preference speed queried in the environmental noise constraint table based on the latest collected vehicle GPS location information. ; S72. Optimal rotational speed calculated based on the latest cycle. Compared with the actual operating speed of the previous cycle Calculate the rate of change of rotational speed When the rate of change of rotational speed exceeds the preset threshold If the optimal speed is then smoothed and filtered before being sent out; Rate of change of rotational speed The calculation formula is as follows: ; In the formula: The optimal speed is calculated for the current control cycle. This refers to the actual operating speed of the range extender in the previous control cycle. To control the cycle, The rate of change of rotational speed, To control the number of cycles; The smoothing filtering process uses a first-order low-pass filtering algorithm, the formula of which is as follows: ; In the formula: This is the actual speed command value sent to the range extender controller after smoothing and filtering. These are the filter coefficients. The optimal speed is calculated for the current control cycle. This refers to the actual operating speed of the range extender in the previous control cycle. To control the number of cycles.

[0029] The system will calculate With the preset threshold When comparing, At that time, directly As an instruction issued, when If the speed command changes too rapidly, it indicates that the speed command is changing too quickly. To avoid load shock to the range extender and abnormal noise, the above-mentioned smoothing filtering algorithm is activated to adjust the calculated speed. Issued as a final instruction; This step, by introducing quantified rate of change judgment and explicit filtering algorithm, transforms the qualitative strategy of preventing sudden speed changes into a quantitative control that can be accurately executed, thereby enhancing the smoothness and reliability of system operation.

[0030] S8 includes the following steps: S81. Continuously monitor battery status parameters, vehicle status parameters and environmental information throughout the entire charging cycle; S82. When any of the following conditions are monitored, a charging termination signal is generated: the intermittent charging command is manually turned off, the vehicle speed is not zero, the remaining fuel level of the vehicle is lower than the third fuel level threshold, the battery temperature exceeds the preset operating temperature range, someone is detected in the vehicle, and the smart key is detected. The preset operating temperature range of the power battery can be set to 0℃ to 45℃. The first fuel level threshold, the second fuel level threshold, and the third fuel level threshold can be set according to the vehicle model, and can be set to 20%, 10%, and 15% of the total fuel tank capacity, respectively. S83. Based on the charging termination signal, the vehicle controller sends a shutdown command to the range extender controller to shut down the range extender and sequentially power down the high-voltage system and the low-voltage system, so that the vehicle returns to sleep mode.

[0031] The system includes: The status monitoring and permission judgment module periodically monitors the status of the power battery through the battery management unit, and wakes up the system when the battery state of charge is lower than the threshold. The system generates a basic charging permission signal by combining the vehicle speed, fuel level, presence of personnel and intermittent charging commands through the environment and vehicle status verification unit. The multimodal data acquisition module receives the basic charging permission signal, obtains the real-time battery status through the battery parameter acquisition unit, reads the vehicle status and environmental information through the vehicle bus interface unit, and calls the pre-stored range extender efficiency MAP and environmental noise constraint table through the model loading unit. The SOC status fuzzy evaluation module, based on the SOC value in the real-time battery status, sets the trapezoidal membership function of low, medium and high power demand intervals through the fuzzy interval definition unit, and outputs the membership degree of the current SOC to each power demand interval through the membership degree calculation unit. The multi-objective optimization decision module receives the membership degree, determines the final power generation by combining the target power calculation unit with the battery physical constraints, and constructs a comprehensive scoring function in the optimization solution unit based on fuel economy, noise and power following performance, and iterates through the range extender efficiency MAP to solve for the optimal speed and optimal torque. The safety rule fusion and instruction generation module receives the optimal speed and optimal torque, performs multi-level condition verification through the safety decision tree unit, and generates speed and torque control instructions and safety intervention instructions by the control instruction encapsulation unit. The dynamic adjustment and monitoring module periodically triggers the multimodal data acquisition module to re-execute the safety rule fusion and instruction generation module during the charging process. It dynamically adjusts the operating point through the operating point update unit and outputs a charging termination signal through the termination condition judgment unit when the condition is not met, thereby controlling the range extender to shut down.

[0032] A self-starting charging method and system operation steps for a range-extended electric vehicle are as follows: Step 1: Status Monitoring and System Wake-up When the vehicle is powered off and the user-preset intermittent charging function is enabled, the system begins monitoring. First, the battery management system periodically wakes up to monitor the state of charge (SOC) of the power battery. When the SOC value is lower than the preset wake-up threshold, the battery management system requests to wake up the vehicle controller. After the vehicle controller is woken up, it will comprehensively verify several basic safety conditions, including: whether the vehicle is stationary, whether there is anyone in the vehicle, whether there is sufficient fuel remaining, whether the battery temperature is within the normal operating range, and whether the intermittent charging command is still enabled. Only when all these conditions are met simultaneously will the system generate a basic charging permission and enter the actual charging decision process.

[0033] Step 2: Multi-source information acquisition and model loading: After obtaining charging permission, the system enters the data preparation phase, which extensively collects the required information from the vehicle network and various sensors, mainly including three categories: battery status parameters, vehicle status parameters, and environmental information. At the same time, the system loads two key data models from memory: one is the range extender efficiency MAP, which is a graph reflecting the fuel consumption rate of the range extender under different speed and torque conditions; the other is the environmental noise constraint table, which is a rule table that defines the maximum allowable operating noise level in different geographical locations, providing constraints for subsequent optimization.

[0034] Step 3: Battery demand assessment based on fuzzy logic: This step is one of the innovative aspects of the entire method. It precisely quantifies the battery's charging needs. The system uses fuzzy logic control theory and predefines three power demand intervals: low, medium, and high. Each interval is described by a trapezoidal membership function. The real-time battery SOC value collected in the second step is substituted into these functions to calculate the degree to which the SOC value belongs to low, medium, and high demand, respectively. This evaluation method overcomes the rigidity problem of traditional fixed thresholds and can more smoothly and accurately reflect the true demand intensity of the battery under boundary power conditions.

[0035] Step 4: Multi-objective optimization decision-making for power generation conditions: This step is another core step, responsible for determining the optimal power generation operating point. First, the system uses the three membership degrees obtained in the third step to perform a weighted calculation to obtain a preliminary target power generation. Then, the target power is corrected based on the physical characteristics of the battery to determine the final power generation. Next, the system constructs a multi-objective optimization function, which aims to simultaneously pursue: optimal fuel economy, minimum operating noise, and best tracking of the final power generation. In the range extender efficiency MAP, under the conditions of satisfying constraints such as noise and power, the system traverses all speed and torque combinations to find the operating point that makes the above multi-objective optimization function score optimal, and outputs the speed and torque at that point as the optimal speed and optimal torque.

[0036] Step 5: Integration of security rules and review of instructions: To ensure absolute safety, before issuing and executing the optimal operating condition command, the system introduces an independent safety decision tree for final verification. The decision tree checks a series of hard safety rules in sequence. Only after passing the verification of all safety nodes will the control command containing the optimal speed and optimal torque be generated. When any safety rule is triggered, the system will generate a corresponding safety intervention command and will not execute an unsafe charging command.

[0037] Step 6: Issuance of control commands and start-up of the range extender: After the control command passes the security verification, the vehicle controller encapsulates it into a standard network message and sends it to the range extender controller via the bus. After receiving the command, the range extender controller first controls the motor to drive the engine to rotate to the preset speed, and then ignites and starts the engine. After the engine starts successfully, the range extender system switches to the power generation mode, controls the engine to run stably at the optimal speed and optimal torque operating point determined in the fourth step, and begins to output electrical energy to charge the power battery.

[0038] Step 7: Cyclic Monitoring and Dynamic Adjustment The charging process is not a one-off transaction, but a dynamically adjusted closed loop. The system repeats the complete process from step two to step six at fixed time intervals. This means that the system will continuously collect the latest battery, vehicle, and environmental data, reassess the needs, perform multi-objective optimization again, and generate new control commands after safety review. In this way, the power generation and range extender operating point are adjusted in real time and smoothly according to the rise of battery SOC, changes in environmental location, and temperature changes, always maintaining an overall optimal state.

[0039] Step 8: Termination Condition Monitoring and Process End: Throughout the charging process, the system continuously monitors all conditions related to basic charging permits and safety rules. Once any termination condition is detected, the system will immediately generate a charging termination signal. Subsequently, the vehicle controller will send a shutdown command to the range extender controller to control the range extender to shut down smoothly and power down in an orderly manner, so that the vehicle returns to a safe dormant state, thereby ending the entire automatic charging process.

[0040] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0041] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A self-starting charging method for a range-extended electric vehicle, characterized in that, The method includes the following steps: S1. When the vehicle is in a powered-off state and receives an intermittent charging command start signal, perform battery status and external environment status monitoring, and wake up the vehicle controller when the basic charging permission conditions are met. S2. Collect battery status parameters, environmental information and vehicle status parameters, and load the preset range extender efficiency MAP and environmental noise constraint table. S3. Evaluate the collected battery state of charge (SOC) value based on fuzzy logic, and calculate the membership degree of the SOC value to the low power demand range, medium power demand range, and high power demand range. S4. Calculate the target power generation based on the membership degree weighting, determine the final power generation in combination with the battery physical constraints, and take the optimal fuel economy, minimum operating noise and best following of the final power generation of the range extender as the comprehensive optimization objectives. Perform multi-objective optimization within the constraints of the range extender efficiency MAP to generate the optimal speed and optimal torque. S5. Perform a safety review of the optimal speed and the optimal torque based on the safety rule decision tree, and generate a reviewed speed control command and torque control command. S6. Send the speed control command and the torque control command to the range extender controller to control the range extender to start and run at the corresponding optimal speed operating point to charge the power battery. S7. During the charging process, S2 to S6 are repeated at fixed intervals to dynamically update the optimal speed and the optimal torque; S8. When the battery status parameters, vehicle status parameters, and environmental information do not meet the basic charging permit conditions and safety rules, control the range extender to shut down and end the charging process.

2. The self-starting charging method for a range-extended electric vehicle according to claim 1, characterized in that, S1 includes the following steps: S11. The battery management system wakes up automatically based on an internal clock and a preset cycle, and continuously monitors the voltage, temperature and internal resistance signals of the power battery. S12. When the state of charge (SOC) value of the power battery is detected to be lower than the preset wake-up threshold, the battery management system sends a wake-up request message to the vehicle controller via the CAN bus. S13. After the vehicle controller is woken up, it reads the vehicle speed signal, remaining fuel signal, battery temperature signal, in-vehicle occupant monitoring signal, and the status of the intermittent charging command. S14. When the following conditions are met simultaneously, a basic charging permission signal is generated: the intermittent charging command is in the on state, the vehicle speed is zero, the remaining fuel is greater than the first fuel threshold, the battery temperature is within the preset operating temperature range, and there is no one in the vehicle.

3. The self-starting charging method for a range-extended electric vehicle according to claim 2, characterized in that, S2 includes the following steps: S21. Obtain the current battery SOC value, battery temperature, battery internal resistance and battery open circuit voltage from the battery management system; S22. Obtain occupant monitoring signals, vehicle GPS location information, and range extender coolant temperature from environmental sensors and body controller; S23. Obtain vehicle remaining fuel information from the CAN bus; S24. Retrieve the range extender efficiency MAP from the memory of the vehicle controller. The range extender efficiency MAP is a data mapping table characterizing the fuel consumption rate of the range extender under different speed and torque conditions. S25. Retrieve the environmental noise constraint table from the memory of the vehicle controller. The environmental noise constraint table defines the maximum operating noise level of the range extender allowed in different geographical locations.

4. The self-starting charging method for a range-extended electric vehicle according to claim 3, characterized in that, S3 includes the following steps: S31. Define fuzzy power demand intervals for SOC values, including low power demand intervals, medium power demand intervals, and high power demand intervals. Each interval is described using a trapezoidal membership function. Among them, the trapezoidal parameters of the low power demand range for Its membership function is: ； Trapezoidal parameters of the medium power demand range for Its membership function is: ； Trapezoidal parameters of the high power demand range for Its membership function is: ; S32. Substitute the current battery SOC value into the trapezoidal membership function to calculate its membership degree values ​​for low, medium, and high power demand ranges, respectively. , and .

5. The self-starting charging method for a range-extended electric vehicle according to claim 4, characterized in that, S4 includes the following steps: S41, Based on the membership degree , and Weighted calculations were performed to obtain the preliminary target power generation. The calculation formula is: ; in, , , Preset rated power generation capacity corresponding to high, medium and low charging demand levels respectively; S42. Calculate the maximum acceptable charging power of the current power battery based on the battery open-circuit voltage and the battery internal resistance. ; S43. Compare the preliminary target power generation. With the maximum acceptable charging power The smaller value among them is determined as the final power generation. ; S44, Construct a system based on the range extender speed and output torque For multi-objective optimization functions of decision variables: ； in, For comprehensive scoring, , , These are the weight coefficients obtained through training with historical data. The preferred rotational speed is obtained by querying the environmental noise constraint table using the vehicle's GPS location information. This refers to the final power generation capacity. S45. Under the conditions of satisfying the specified speed range, torque range, estimated operating noise not exceeding the maximum operating noise level, and actual power generation not less than 0.8 times the final power generation. Under the constraints, the discrete operating points in the range extender efficiency MAP are traversed, and the comprehensive score for each feasible point is calculated. ; S46. Select the comprehensive score The minimum operating point is used to output the optimal speed and torque.

6. The self-starting charging method for a range-extended electric vehicle according to claim 5, characterized in that, S5 includes the following steps: S51. Establish an independent security decision tree, which contains multiple layers of decision nodes; S52. Input the optimal speed, the optimal torque, the real-time collected vehicle status parameters and environmental information into the safety decision tree; S53. The safety decision tree executes judgments in sequence: when the smart key is detected inside the vehicle and the vehicle occupant monitoring signal indicates that someone is inside, the range extender stop command is output; when the battery temperature is detected to exceed the first safety threshold, the power reduction operation mode is triggered, and the optimal speed and optimal torque after power reduction are recalculated; when the remaining fuel level of the vehicle is detected to be lower than the second fuel level threshold, the range extender stop command is output. S54. When all safety judgment nodes are passed, the speed control command and the torque control command containing the optimal speed and the optimal torque are generated. When any safety rule is triggered, the corresponding safety control command is generated.

7. The self-starting charging method for a range-extended electric vehicle according to claim 6, characterized in that, S6 includes the following steps: S61. The vehicle controller encapsulates the speed control command and the torque control command into a torque request message in speed mode and sends it to the range extender controller via the CAN bus. S62. The range extender controller controls the generator to operate as a motor, powered by the power battery to drive the engine to a preset ignition speed; S63. When the engine reaches the preset ignition speed, the range extender controller sends an ignition enable signal to the engine controller to control the engine fuel injection and ignition. S64. After the engine is successfully ignited, the range extender controller switches to speed mode, controls the generator to be driven by the engine, and outputs electrical energy through the inverter according to the operating point corresponding to the optimal speed and the optimal torque to charge the power battery.

8. The self-starting charging method for a range-extended electric vehicle according to claim 7, characterized in that, In step S7, the fixed-period repetitive execution process further includes the following steps: S71. During each cycle execution, based on the latest collected vehicle GPS location information, dynamically update the environmental preference speed queried in the environmental noise constraint table. ; S72. Calculate the speed change rate based on the optimal speed calculated in the latest cycle and the actual operating speed in the previous cycle. When the speed change rate exceeds a preset threshold, perform smoothing filtering on the optimal speed before sending it out.

9. A self-starting charging method for a range-extended electric vehicle according to claim 8, characterized in that, S8 includes the following steps: S81. Throughout the entire charging cycle, continuously monitor the battery status parameters, vehicle status parameters, and environmental information; S82. When any of the following conditions are monitored, a charging termination signal is generated: the intermittent charging command is manually turned off, the vehicle speed is not zero, the remaining fuel level of the vehicle is lower than the third fuel level threshold, the battery temperature exceeds the preset operating temperature range, someone is detected in the vehicle, and the smart key is detected. S83. Based on the charging termination signal, the vehicle controller sends a shutdown command to the range extender controller to shut down the range extender and sequentially power down the high-voltage system and the low-voltage system, so that the vehicle returns to a dormant state.

10. A self-starting charging system for a range-extended electric vehicle, used to implement the self-starting charging method for a range-extended electric vehicle as described in any one of claims 1-9, characterized in that, The system includes: The status monitoring and permission judgment module periodically monitors the status of the power battery through the battery management unit, and wakes up the system when the battery state of charge is lower than the threshold. The system generates a basic charging permission signal by combining the vehicle speed, fuel level, presence of personnel and intermittent charging commands through the environment and vehicle status verification unit. The multimodal data acquisition module receives the basic charging permission signal, obtains the real-time battery status through the battery parameter acquisition unit, reads the vehicle status and environmental information through the vehicle bus interface unit, and calls the pre-stored range extender efficiency MAP and environmental noise constraint table through the model loading unit. The SOC state fuzzy evaluation module, based on the SOC value in the real-time battery state, sets the trapezoidal membership function of low, medium and high power demand intervals through the fuzzy interval definition unit, and outputs the membership degree of the current SOC to each power demand interval through the membership degree calculation unit. The multi-objective optimization decision module receives the membership degree, determines the final power generation by combining the target power calculation unit with the battery physical constraints, and constructs a comprehensive scoring function in the optimization solution unit based on fuel economy, noise and power following performance, and iterates through the range extender efficiency MAP to solve for the optimal speed and optimal torque. The safety rule fusion and instruction generation module receives the optimal speed and optimal torque, performs multi-level condition verification through the safety decision tree unit, and generates speed and torque control instructions and safety intervention instructions by the control instruction encapsulation unit. The dynamic adjustment and monitoring module periodically triggers the multimodal data acquisition module to re-execute the safety rule fusion and instruction generation module during the charging process. It dynamically adjusts the operating point through the operating point update unit and outputs a charging termination signal through the termination condition judgment unit when the condition is not met, thereby controlling the range extender to shut down.

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