Control method and system for automobile with range extender
Through the redundant dual-battery structure and intelligent energy management strategy, the problem of single battery deep discharge and range extender control mode in traditional extended-range vehicles is solved, and battery life is extended, energy utilization is improved and vehicle adaptability is enhanced.
Patent Information
- Application Number
- CN202510751646.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-06
- Publication Date
- 2025-08-15
AI Technical Summary
Traditional extended-range vehicles have frequent deep discharges due to small single-cell SOC, which affects battery life. The single range extender control mode leads to NVH deterioration and energy waste, and the fault tolerance rate is low.
The redundant dual battery structure and intelligent energy management control strategy are adopted, and the intervention status of the range extender is dynamically adjusted through the vehicle controller, combined with the data perception analysis module to accurately match the vehicle driving status, and set multi-stage state of charge thresholds and scene correction coefficients to achieve coordinated power supply between the range extender and the battery.
It improves battery life, reduces energy waste, improves the vehicle's ability to adapt to complex road conditions, and reduces fuel consumption and usage costs.
Smart Images
Figure CN120481986A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of new energy vehicle control technology, and in particular to a control method and system for a range extender vehicle. Background Art
[0002] New energy vehicles that use range extenders are additionally equipped with a range extender. Unlike pure electric drive, range extenders use a built-in battery to drive the motor in pure electric drive mode. When the battery SOC falls below a set threshold, the range extender is activated to directly drive the motor and charge the battery. However, traditional range extenders have the following problems: 1. Single battery system defects: Because traditional range extenders have a low single battery SOC, the battery will frequently undergo deep discharge and more cycles, which can easily lead to lithium deposition or SEI film rupture, affecting battery life; 2. The range extender has a single control mode: It uses a fixed threshold intervention, such as forcing the range extender to start only after the battery SOC falls below a certain percentage. In addition, the range extender frequently starts and stops when the battery SOC is low, resulting in worse NVH and energy waste; 3. Low fault tolerance: Failure of a single battery or range extender can easily cause system paralysis.
[0003] Therefore, it is very necessary to provide a control method and system for a range extender vehicle, adopt an intelligent energy management control strategy, implement hierarchical monitoring and dynamic coordination mechanism, and better realize the integration of the range extender and the battery. Summary of the Invention
[0004] In view of this, the present invention proposes a control method and system for a range extender vehicle that adopts a redundant dual-battery structure, reduces the number of deep discharges of the battery, and ensures that the range extender is in a high-efficiency output condition after being activated.
[0005] In one aspect, the present invention provides a control method for a vehicle with a range extender, comprising the following steps: S1: The range-extended vehicle is equipped with a vehicle controller, a range extender, two energy storage batteries, and a drive motor. The vehicle controller is used to obtain the charge status of the two energy storage batteries and the operating status of the drive motor, and adjust the intervention status of the range extender; S2: After the extended-range vehicle is powered on, the vehicle controller first obtains the charge status of the two energy storage batteries and the on / off status of the range extender; S3: The vehicle controller determines the operating status of the vehicle: if the vehicle is stationary, the vehicle controller executes a first power supply strategy including the range extender based on the power levels of the two energy storage batteries; if the vehicle is in motion, the vehicle controller executes a second power supply strategy including the range extender.
[0006] On the basis of the above technical solution, preferably, the two energy storage batteries are the first battery and the second battery; the first power supply strategy includes the following situations: 1) When the vehicle controller collects that the SOC of the first battery and the second battery is greater than the first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor; 2) When the vehicle controller collects that the SOC of the first battery is greater than the first threshold and the SOC of the second battery is less than the first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and at the same time, the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 3) When the vehicle controller collects that the SOC of the first battery and the second battery are both less than the first threshold, and both are greater than the second threshold When the first threshold is greater than the second threshold, the battery with the higher SOC between the first and second batteries is selected to power the drive motor, and the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 4) When the vehicle controller detects that the SOC of the first battery is ≤ the second threshold, and the second threshold < the SOC of the second battery is ≤ the first threshold, the battery with the higher SOC between the first and second batteries is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC; 5) When the vehicle controller detects that the SOC of the first battery and the second battery is ≤ the second threshold, the battery with the higher SOC between the first and second batteries is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC.
[0007] Preferably, the rated capacities of the first battery and the second battery are the same or different.
[0008] Preferably, the second power supply strategy includes the following situations: 1) when the vehicle controller detects that the SOC of the first battery and the second battery are both greater than the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor; 2) when the vehicle controller detects that the SOC of the first battery is greater than the second threshold and the SOC of the second battery is ≤ the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and at the same time, the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 3) when the vehicle controller detects that the SOC of the first battery and the second battery are both ≤ the second threshold and both are greater than the third threshold, the second threshold is greater than the third threshold, and the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor , and the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with a lower SOC; 4) When the vehicle controller detects that the SOC of the first battery is ≤ the third threshold, and the third threshold is < the SOC of the second battery ≤ the second threshold, the battery with the higher SOC between the first battery and the second battery is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with a lower SOC; 5) When the vehicle controller detects that the SOC of the first battery and the second battery is ≤ the third threshold, the range extender is forcibly turned on to directly provide output power to the drive motor, entering limp home mode, limiting the output power of the range extender to the drive motor, and the remaining output power is used to charge the battery with a lower SOC; if the user manually turns off the range extender at this time, the first battery and the second battery are connected in parallel to power the drive motor.
[0009] More preferably, the first threshold S 1 is 50% of the rated capacity of the first battery and the second battery, the second threshold S 2 is 20% of the rated capacity of the first battery and the second battery, the third threshold S 3 is 10% of the rated capacity of the first battery and the second battery.
[0010] Further preferably, the vehicle controller also includes a data perception and analysis module, which is used to obtain the current vehicle location and road conditions, construct a power demand model for the drive motor, and then estimate the power distribution output relationship between the first battery and the second battery in different intervals when the vehicle is driving.
[0011] Further preferably, the power demand model of the driving motor is constructed according to the following formula: Model: ,in is the real-time vehicle speed, is the transmission efficiency of the drive motor, is the mass of the vehicle, is the acceleration due to gravity, is the road slope, is the rolling resistance coefficient, is the air density, C d is the drag coefficient, A is the equivalent area of the vehicle in the windward direction, is the vehicle acceleration, is the scene correction factor.
[0012] Preferably, the power distribution output relationship between the first battery and the second battery in different intervals when estimating the vehicle is in a driving state is to establish the following conditional relationship: , among which is the output power of the first battery and the second battery, are the state of charge SOC of the first battery and the second battery respectively, The power distribution ratio of the range extender after the user manually turns on the range extender. is the output power of the range extender, is the output power limit coefficient of limp home mode, max and min are the maximum and minimum value functions respectively, P is the input power provided to the drive motor.
[0013] Preferably, the scenario correction coefficient is obtained by combining a single scenario among a hill climbing scenario, a city congestion scenario, a high-speed cruising scenario and a vehicle maximum power output scenario, or by combining two or more different scenarios.
[0014] In another aspect, the present invention provides a control system for a vehicle with a range extender, for implementing the control method for the vehicle with a range extender, comprising a vehicle controller, a first battery, a second battery, a drive motor, and a range extender, and further comprising: An engine controller, connected to the range extender and the vehicle controller, is used to drive the engine and provide the engine power to the first battery, the second battery and / or the drive motor; The motor controller is connected to the vehicle controller and the drive motor signal respectively, and is used to receive instructions from the vehicle controller and distribute the output power of the first battery, the second battery and the range extender to the drive motor; The battery controller is connected to the vehicle controller, the first battery, and the second battery respectively, and is used to obtain the state of charge of the first battery and the second battery, and receive instructions from the vehicle controller to adjust the output state or charging state of the first battery and the second battery; Among them, the vehicle controller also executes the first power supply strategy or the second power supply strategy including the range extender based on the charge status of the first battery and the second battery fed back by the battery controller and the current status of the vehicle.
[0015] The present invention provides a control method and system for a range extender vehicle, which has the following advantages over the prior art: (1) By equipping dual batteries with collaborative optimization and redundant structure, the SOC differences of different batteries are effectively utilized to achieve dynamic power supply selection, significantly improving energy utilization, reducing the shortcomings of frequent deep discharge of single batteries, and helping to increase battery life; by segmenting the battery SOC state, different power supply strategies are selected according to the different driving conditions of the vehicle, avoiding long-term overcharge or over-discharge of the battery, and extending the battery life; (2) Based on the driving environment acquired by the data perception and analysis module, a scenario correction coefficient is introduced, and a power demand model for the drive motor is further constructed. The vehicle's driving state is segmented into scenarios to achieve accurate power demand matching, reducing energy waste while improving the vehicle's adaptability to complex road conditions. (3) It provides an interactive function of autonomous judgment of the three-level threshold of charge state and user-initiated activation of the range extender. The range extender is forced to start only when the battery is at a low charge state, which can save fuel consumption, extend the pure electric driving range, and reduce the cost of vehicle use. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0017] Figure 1 This is a flow chart of a control method and system for a range extender vehicle according to the present invention; Figure 2 The present invention provides a system structure block diagram of a control method and system for a range extender vehicle. DETAILED DESCRIPTION
[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0019] Traditional range-extended vehicles have the following defects: due to the low SOC of a single battery, the battery will frequently undergo deep discharge, resulting in more cycles and affecting the battery life; the range extender has a single control mode, using a fixed threshold intervention, and the range extender frequently starts and stops when the battery SOC is low; and the fault tolerance rate is low. In view of this, Figure 1 As shown, on the one hand, the present invention provides a control method for a vehicle with a range extender, comprising the following steps: S1: The range-extended vehicle is equipped with a vehicle controller, a range extender, two energy storage batteries and a drive motor. The vehicle controller is used to obtain the charge status of the two energy storage batteries and the working status of the drive motor, and adjust the intervention status of the range extender.
[0020] It should be noted that the capacities of the two energy storage batteries may be the same or different.
[0021] S2: After the extended-range vehicle is powered on, the vehicle controller first obtains the charge status of the two energy storage batteries and the on / off status of the range extender.
[0022] S3: The vehicle controller determines the operating status of the vehicle: if the vehicle is stationary, the vehicle controller executes a first power supply strategy including the range extender based on the power levels of the two energy storage batteries; if the vehicle is in motion, the vehicle controller executes a second power supply strategy including the range extender.
[0023] The specific content is: let the two energy storage batteries be the first battery and the second battery; the first power supply strategy includes the following situations: 1) When the vehicle controller collects the SOC of the first battery and the second battery> the first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor; 2) When the vehicle controller collects the SOC of the first battery> the first threshold and the SOC of the second battery≤ the first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and at the same time the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 3) When the vehicle controller collects the SOC of the first battery and the second battery are both ≤ the first threshold, and both are greater than the second threshold, the first threshold When the SOC of the first battery is less than or equal to the second threshold, the battery with the higher SOC between the first and second batteries is selected to power the drive motor, and the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 4) When the vehicle controller detects that the SOC of the first battery is less than or equal to the second threshold, and the second threshold is less than or equal to the SOC of the second battery less than or equal to the first threshold, the battery with the higher SOC between the first and second batteries is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC; 5) When the vehicle controller detects that the SOC of the first battery and the second battery is less than or equal to the second threshold, the battery with the higher SOC between the first and second batteries is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC.
[0024] The first power supply strategy is to ensure the reliable operation of onboard equipment when the vehicle is parked, such as the use of onboard air conditioning, car audio, or onboard multimedia devices, and to reserve sufficient power for possible vehicle driving.
[0025] Among them, the second power supply strategy includes the following situations: 1) When the vehicle controller collects that the SOC of the first battery and the second battery are both greater than the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor; 2) When the vehicle controller collects that the SOC of the first battery is greater than the second threshold and the SOC of the second battery is ≤ the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and at the same time, the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 3) When the vehicle controller collects that the SOC of the first battery and the second battery are both ≤ the second threshold and both are greater than the third threshold, the second threshold is greater than the third threshold, and the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and at the same time The vehicle controller asks the user whether to manually turn on the range extender to charge the battery with a lower SOC; 4) When the vehicle controller detects that the SOC of the first battery is ≤ the third threshold, and the third threshold is < the SOC of the second battery ≤ the second threshold, the battery with the higher SOC between the first battery and the second battery is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with a lower SOC; 5) When the vehicle controller detects that the SOC of the first battery and the second battery is ≤ the third threshold, the range extender is forcibly turned on to directly provide output power to the drive motor, entering limp home mode, limiting the output power of the range extender to the drive motor, and the remaining output power is used to charge the battery with a lower SOC; if the user manually turns off the range extender at this time, the first battery and the second battery are connected in parallel to power the drive motor.
[0026] Limp home mode is a low-speed, low-power driving state, typically used when the battery is low or the battery temperature is too high.
[0027] In this embodiment, the first threshold is set S 1 is 50% of the rated capacity of the first battery and the second battery, the second threshold S 2 is 20% of the rated capacity of the first battery and the second battery, the third threshold S 3 is 10% of the rated capacity of the first battery and the second battery. In practice, depending on the type of battery, the above-given value may fluctuate within a certain range, and the above-given threshold value is adjustable.
[0028] In order to accurately match the power requirements of the vehicle under the corresponding road conditions, realize the precise intervention of the range extender, ensure that the range extender is in an efficient output state, and save fuel consumption, in one embodiment, the vehicle controller also includes a data perception and analysis module. The data perception and analysis module obtains parameters such as the vehicle's position, current speed, and acceleration by configuring a positioning system, a vehicle speed sensor, and an on-board communication device, and obtains road conditions and congestion conditions through the Internet. The road conditions here can include flat ground, uphill, congested, frequently started and stopped urban roads, highways, or high-power output occasions.
[0029] The data perception and analysis module is used to obtain the current vehicle location and road conditions, build a power demand model for the drive motor, and then estimate the power distribution output relationship between the first battery and the second battery in different intervals when the vehicle is in motion.
[0030] Among them, the power demand model of the drive motor is established according to the following formula Model: ,in is the real-time vehicle speed, is the transmission efficiency of the drive motor, is the mass of the vehicle, is the acceleration due to gravity, is the road slope, is the rolling resistance coefficient, is the air density, C d is the drag coefficient, A is the equivalent area of the vehicle in the windward direction, is the vehicle acceleration, The last 15% is a safety margin reserved to account for power requirements affected by weather, ambient temperature, and other factors.
[0031] Among them, the scene correction coefficient It is obtained by combining a single scenario among the climbing scenario, urban congestion scenario, high-speed cruising scenario and vehicle maximum power output scenario, or by combining two or more different scenarios. Specifically, the scenario correction coefficient is divided into the following four types: i , : Correction coefficient for long uphill sections , Correction coefficient for urban congested road scenes , high-speed cruise section scene correction coefficient Correction factor for long-term high-power output road sections , the corresponding scene correction coefficient expressions are: , that is, when the slope does not exceed 5° and the slope is greater than 5°, the long uphill section scene correction coefficient There are slight differences, the former is a quadratic polynomial fit, and the latter is a linear fit; ,in is the average interval time between congested sections of the city, in seconds; ,The distance between vehicles in the high-speed cruising section is larger, and the speed is more stable; , here T is the maximum temperature of the first battery or the second battery at power output, Indicates the time the drive motor continuously operates at more than 80% of the rated power, in seconds. The timing starts from the first time the input power of the drive motor reaches 80% of the rated power. This setting is to ensure that the battery does not generate excessive heat when the battery is fully output. When the battery temperature rises, if the temperature threshold of 50 degrees Celsius is reached, the power output will be reduced. For example, the input power of the drive motor is limited to 50%-60% of the rated power to avoid continuous high-load output causing the battery temperature to rise too quickly.
[0032] If only a single scenario type is affected, the power requirement The scenario influence term in the model , can be rewritten as The above four scene types can be combined arbitrarily. For example, if the long uphill section and the high-speed cruising section are combined, the scene influence item used is , and so on.
[0033] In addition, to estimate the power distribution output relationship between the first battery and the second battery in different intervals when the vehicle is in motion, the following conditional relationship is established: , among which is the output power of the first battery and the second battery, are the state of charge SOC of the first battery and the second battery respectively, The power distribution ratio of the range extender after the user manually turns on the range extender. is the output power of the range extender, is the output power limit coefficient of limp home mode, max and min are the maximum and minimum value functions respectively. P For the actual input power provided to the drive motor, the first item in the conditional relationship corresponds to situation 1) or situation 2 in the second power supply strategy; the second item in the conditional relationship corresponds to situation 3) or situation 4 in the second power supply strategy; the third item in the conditional relationship corresponds to situation 5) in the second power supply strategy.
[0034] In another aspect, the present invention provides a control system for a vehicle with a range extender, for implementing the control method for the vehicle with a range extender, comprising a vehicle controller, a first battery, a second battery, a drive motor, and a range extender, and further comprising: an engine controller, signal-connected to the range extender and the vehicle controller, for driving the engine to provide power to the first battery, the second battery, and / or the drive motor; the engine controller starts the engine corresponding to the range extender, and the engine output torque can be directly transmitted to the drive motor, or it can drive a generator to charge the first battery or the second battery, and the battery provides input power to the drive motor; The motor controller is connected to the vehicle controller and the drive motor signal respectively, and is used to receive instructions from the vehicle controller and distribute the output power of the first battery, the second battery and the range extender to the drive motor; The battery controller is connected to the vehicle controller, the first battery, and the second battery respectively, and is used to obtain the state of charge of the first battery and the second battery, and receive instructions from the vehicle controller to adjust the output state or charging state of the first battery and the second battery; Among them, the vehicle controller also executes the first power supply strategy or the second power supply strategy including the range extender based on the charge status of the first battery and the second battery fed back by the battery controller and the current status of the vehicle.
[0035] Combined with attachment Figure 2 It can be seen that the drive motor is also connected to the drive wheel through a speed reducer; Figure 2 Battery 1 and Battery 2 in the figure correspond to the aforementioned first and second batteries, respectively. In either the first or second power supply strategy, when the vehicle controller inquires about whether to manually activate the range extender to charge the battery with a lower SOC, the user can manually activate or deactivate the range extender through a user input interface, such as the central control touchscreen.
[0036] The present invention has the following advantages: The dual-battery redundant structure improves the problem of a single battery with many charge and discharge cycles and a large depth of discharge; Dynamic and scenario-based range extender control: Setting three-level threshold control to improve NVH deterioration and energy waste. The range extender solves the problem of frequent starts and stops at low SOC. Adhering to the principle of "no start unless necessary", once the range extender is started, it is kept operating at a high efficiency state as much as possible. The power system with dual batteries and a range extender has a high fault tolerance rate. The range extender can not only charge but also directly drive the drive motor. The range extender maximizes power utilization, precisely matching power output with typical vehicle driving scenarios, avoiding redundant configurations of traditional high-power range extenders. The range extender's output power is more closely aligned with vehicle needs.
[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A control method for a vehicle with a range extender, characterized in that: The steps include: S1: The range-extended vehicle is equipped with a vehicle controller, a range extender, two energy storage batteries, and a drive motor. The vehicle controller is used to obtain the charge status of the two energy storage batteries and the operating status of the drive motor, and adjust the intervention status of the range extender; S2: After the extended-range vehicle is powered on, the vehicle controller first obtains the charge status of the two energy storage batteries and the on / off status of the range extender; S3: The vehicle controller determines the operating status of the vehicle: if the vehicle is stationary, the vehicle controller executes a first power supply strategy including the range extender based on the power levels of the two energy storage batteries; if the vehicle is in motion, the vehicle controller executes a second power supply strategy including the range extender.
2. The control method for a range extender vehicle according to claim 1, characterized in that: The two energy storage batteries are designated as a first battery and a second battery. The first power supply strategy includes the following situations: 1) when the vehicle controller detects that the SOC of the first battery and the second battery is greater than a first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor; 2) When the vehicle controller detects that the SOC of the first battery is greater than the first threshold and the SOC of the second battery is less than or equal to the first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 3) When the vehicle controller detects that the SOCs of the first battery and the second battery are both less than or equal to the first threshold and both are greater than the second threshold, and the first threshold is greater than the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the vehicle controller asks the user whether to manually turn on the range extender to charge the battery with the lower SOC; 4) When the vehicle controller detects that the SOC of the first battery is less than or equal to the second threshold, and the second threshold is less than or equal to the SOC of the second battery less than or equal to the first threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC; 5) When the vehicle controller detects that the SOCs of the first battery and the second battery are less than or equal to the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC.
3. The control method for a range extender vehicle according to claim 2, characterized in that: The rated capacities of the first battery and the second battery are the same or different.
4. The control method for a range extender vehicle according to claim 2, characterized in that: The second power supply strategy includes the following situations: 1) when the vehicle controller detects that the SOCs of the first battery and the second battery are both greater than a second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor; 2) When the vehicle controller detects that the SOC of the first battery is greater than the second threshold and the SOC of the second battery is less than or equal to the second threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the vehicle controller asks the user whether to manually start the range extender to charge the battery with the lower SOC; 3) When the vehicle controller detects that the SOC of the first battery and the second battery are both less than or equal to the second threshold and both are greater than the third threshold, and the second threshold is greater than the third threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the vehicle controller asks the user whether to manually start the range extender to charge the battery with the lower SOC; 4) When the vehicle controller detects that the SOC of the first battery and the second battery are both less than or equal to the second threshold and both are greater than the third threshold, and the second threshold is greater than the third threshold, the battery with the higher SOC of the first battery and the second battery is selected to power the drive motor, and the vehicle controller asks the user whether to manually start the range extender to charge the battery with the lower SOC; When the vehicle controller detects that the SOC of the first battery is ≤ the third threshold, and the third threshold is less than the SOC of the second battery ≤ the second threshold, the battery with the higher SOC between the first battery and the second battery is selected to power the drive motor, and the range extender is forcibly turned on to charge the battery with the lower SOC; 5) When the vehicle controller detects that the SOC of the first battery and the second battery is ≤ the third threshold, the range extender is forcibly turned on to directly provide output power to the drive motor, entering limp home mode, limiting the output power of the range extender to the drive motor, and the remaining output power is used to charge the battery with the lower SOC; if the user manually turns off the range extender at this time, the first battery and the second battery are connected in parallel to power the drive motor.
5. The control method for a range extender vehicle according to claim 4, characterized in that: First threshold S 1 is 50% of the rated capacity of the first battery and the second battery, the second threshold S 2 is 20% of the rated capacity of the first battery and the second battery, the third threshold S 3 is 10% of the rated capacity of the first battery and the second battery.
6. The control method for a range extender vehicle according to claim 4, characterized in that: The vehicle controller also includes a data perception and analysis module, which is used to obtain the current vehicle location and road conditions, build a power demand model for the drive motor, and then estimate the power distribution output relationship between the first battery and the second battery in different intervals when the vehicle is driving.
7. The control method for a range extender vehicle according to claim 6, characterized in that: The power demand model of the drive motor is constructed according to the following formula: Model: ,in is the real-time vehicle speed, is the transmission efficiency of the drive motor, is the mass of the vehicle, is the acceleration due to gravity, is the road slope, is the rolling resistance coefficient, is the air density, C d is the drag coefficient, A is the equivalent area of the vehicle in the windward direction, is the vehicle acceleration, is the scene correction factor.
8. The control method for a range extender vehicle according to claim 7, characterized in that: The power distribution output relationship between the first battery and the second battery in different intervals when estimating the vehicle's driving state is established by establishing the following conditional relationship: , among which is the output power of the first battery and the second battery, are the state of charge SOC of the first battery and the second battery respectively, The power distribution ratio of the range extender after the user manually turns on the range extender. is the output power of the range extender, is the output power limit coefficient of limp home mode, max and min are the maximum and minimum value functions respectively, P is the input power provided to the drive motor.
9. The control method for a range extender vehicle according to claim 7, characterized in that: The scenario correction coefficient is obtained by combining a single scenario among the hill climbing scenario, the urban congestion scenario, the high-speed cruising scenario and the vehicle maximum power output scenario, or by combining two or more different scenarios.
10. A control system for a vehicle with a range extender, for implementing the method according to any one of claims 2 to 9, comprising a vehicle controller, a first battery, a second battery, a drive motor and a range extender, characterized in that: Also includes: An engine controller, connected to the range extender and the vehicle controller, is used to drive the engine and provide the engine power to the first battery, the second battery and / or the drive motor; The motor controller is connected to the vehicle controller and the drive motor signal respectively, and is used to receive instructions from the vehicle controller and distribute the output power of the first battery, the second battery and the range extender to the drive motor; The battery controller is connected to the vehicle controller, the first battery, and the second battery respectively, and is used to obtain the state of charge of the first battery and the second battery, and receive instructions from the vehicle controller to adjust the output state or charging state of the first battery and the second battery; Among them, the vehicle controller also executes the first power supply strategy or the second power supply strategy including the range extender based on the charge status of the first battery and the second battery fed back by the battery controller and the current status of the vehicle.