Power preservation control method and device of extended-range hybrid system

Abstract

The application is suitable for the technical field of hybrid system control, and provides a power preservation control method and device for a range-extender hybrid system. The method comprises the following steps: determining a driving mode and a battery power permission state to which the system should enter according to real-time power; calculating available driving electric power of the current system based on the battery power permission state and in combination with actual power generation of the range extender and consumed power of accessories; determining a final allowable output upper limit of the driving motor according to a demand driving power or demand rotating speed parsed from a driver power request signal and based on the available driving electric power and the driving mode; and outputting a control instruction to ensure that actual output of the driving motor does not exceed the final allowable output upper limit. The application provides a reliable energy management solution for the range-extender hybrid system by intelligent power preservation control and multi-mode dynamic adjustment, which takes into account the power demand and the endurance on the premise of ensuring system safety and battery life.

Description

Technical Field

[0001] This invention belongs to the field of hybrid system control technology, and particularly relates to a power-saving control method and device for a range-extended hybrid system. Background Technology

[0002] Inland rivers and lakes typically use gasoline-powered motorboats for water recreation, and in some areas, they are also used in agriculture, such as fishing. The exhaust emissions from these gasoline-powered motorboats pollute the environment; the exhaust gases, when in contact with freshwater, can easily cause water acidification, which is detrimental to water resources and environmental protection; furthermore, the engine noise causes noise pollution, and fuel costs are high.

[0003] Compared to gasoline-powered motorboats, electric motorboats avoid environmental pollution from exhaust emissions, engine noise, and fuel costs. However, due to space constraints, electric motorboats have smaller battery capacities, resulting in shorter driving ranges.

[0004] However, due to current technological barriers in power batteries, insufficient range remains the biggest problem for pure electric vehicles and motorboats. To address the range issue of electric motorcycles, range-extended motorcycles are currently a type of motorboat that uses other energy sources (gasoline) to replenish power when the battery is insufficient or depleted. Range-extended vehicles and motorboats have become a key research area before breakthroughs in battery technology. While range-extended vehicle technology is maturing, range-extended motorboats are currently in their infancy. Therefore, it is necessary to design a comprehensive control logic for range-extended motorboats to improve energy management and control, thereby enhancing reliability, power, safety, and range. Summary of the Invention

[0005] The purpose of this invention is to provide a power-saving control method for a range-extended hybrid system, aiming to solve the above-mentioned technical problems.

[0006] This invention is implemented as follows: a power-saving control method for a range-extended hybrid system, the system including a range extender, a drive motor, a battery pack, and accessories, the power-saving control method comprising the following steps: The system acquires operating parameters in real time, including the real-time battery pack charge, motion mode calibration, and driver power request signal. Based on the real-time battery level, determine the driving mode and the battery power permissible state that the system should enter; Based on the battery power permitting status, and combined with the actual power generation of the range extender and the power consumption of the accessories, the available drive power of the current system is calculated. The required drive power or required speed is parsed from the driver's power request signal, and the final allowable output limit of the drive motor is determined based on the available drive power and driving mode. Output control commands to ensure that the actual output of the drive motor does not exceed the final allowable output limit.

[0007] Furthermore, the accessories include an air conditioning compressor and a step-down DC-DC converter; the system also includes a low-voltage unit; the low-voltage unit includes a PDU high-voltage distribution box, a battery, function buttons, and a throttle opening; the range extender includes an engine controller and an ISG motor.

[0008] Furthermore, the driving modes include speed-limited power-saving mode, full-speed mode, and sport mode; the driving mode is determined by judging whether the real-time battery level is greater than the calibrated power-saving threshold. If the real-time power consumption is less than or equal to the calibrated power-saving threshold, the control system adopts a speed-limiting power-saving mode. If the real-time power consumption is greater than the calibrated power consumption threshold, determine whether the motion mode calibration value in the working parameters is set to 1: if the motion mode calibration value in the working parameters is set to 1, the control system adopts motion mode; if the motion mode calibration value in the working parameters is set to 0, the control system adopts full-speed mode.

[0009] Furthermore, the calibrated power reserve threshold is 40%-45%, which is used for power reserve when switching from speed-limited power reserve mode to full-speed mode or sport mode.

[0010] Furthermore, the driving mode is set to full speed according to the maximum speed limit corresponding to the current maximum battery pack charge. The initial value of the current maximum battery pack charge is 40%. The identification update condition 1 is that the throttle opening is less than or equal to 60% and the battery charge increases. The current maximum battery pack charge is equal to the actual charge. When the identification update condition 1 is not met, the system retains the stored value from the previous moment. The second condition for identification and update is that the battery level gradually decreases to below the calibrated power reserve threshold of 40%, and the current maximum battery level is equal to 40% of the actual battery level. If the second condition for identification and update is not met, the system retains the stored value from the previous moment.

[0011] Furthermore, the formula for calculating the available driving electric power is as follows: Available driving electric power = Discharge power of battery pack + Actual power generated by range extender - Power consumed by accessories.

[0012] Furthermore, the battery power permissible state is divided through multi-level power thresholds: If the real-time power level is greater than the upper threshold of the first level power level, the discharge power of the battery pack will be used according to its actual capacity. If the real-time power level is less than the threshold value under the first level of power level, the discharge power of the battery pack will be limited to 0kW; If the real-time battery level is less than the threshold of the second-level battery level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging, indicating a first-level fault of low battery level. If the real-time battery level is less than the threshold of the third level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging. A low battery level level two fault will be indicated, and the device will be shut down. If the real-time battery level is less than the upper threshold of the fourth level, the discharge power of the battery pack will be limited to 0kW, and the charging gun will not be plugged in. A low battery level two fault will be indicated, and the device will be shut down.

[0013] Furthermore, if the real-time battery level is greater than the upper threshold of the fourth level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging. A low battery level level two fault will be indicated, and the device will be shut down and powered off. If the real-time battery level is greater than the upper threshold of the third level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging, indicating a first-level fault of low battery level. If the real-time power level is greater than the upper threshold of the second-level power level, the discharge power of the battery pack will be limited to 0kW; If the real-time battery level is greater than the first-level battery level threshold, the battery pack's discharge power will be used according to its actual capacity.

[0014] Furthermore, based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the first-level power level, then the real-time power level of the battery pack is determined as the first-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the second-level power level, then the real-time power level of the battery pack is determined to be the second-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the third-level power level, then the real-time power level of the battery pack is determined to be the third-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the fourth level power level, then the real-time power level of the battery pack is determined to be the fourth level power level. Wherein, the first level of power is greater than the second level of power, the second level of power is greater than the third level of power, and the third level of power is greater than the fourth level of power.

[0015] Another object of the present invention is to provide a power-saving control device for a range-extended hybrid system, for implementing the above-mentioned power-saving control method for a range-extended hybrid system, comprising: The operating parameter acquisition module is used to acquire the operating parameters of the system in real time. The operating parameters include the real-time battery pack charge, the motion mode calibration value, and the driver's power request signal. The power analysis module is used to determine the driving mode and the battery power permissible state that the system should enter based on the real-time power level. The available drive power calculation module is used to calculate the available drive power of the current system based on the battery power permitting status and in combination with the actual power generated by the range extender and the power consumed by the accessories. The output upper limit determination module is used to parse the required drive power or required speed according to the driver's power request signal, and determine the final allowable output upper limit of the drive motor based on the available drive electric power and driving mode. The control command output module is used to output control commands to ensure that the actual output of the drive motor does not exceed the final allowable output limit.

[0016] The energy management method for a range-extended hybrid system provided by this invention, through intelligent energy management and multi-mode dynamic adjustment, balances range and power requirements while ensuring system safety and battery life, providing a reliable energy management solution for range-extended hybrid systems. Specifically, when the battery level is high, different driving modes are adjusted to rationally protect and manage system energy: for different operating conditions (long and short continuous full-throttle high-power high-speed driving) and system states (multiple driving modes), the method actively identifies the operating conditions and limits the maximum speed of the drive motor to rationally protect and manage system energy, preventing rapid depletion of the battery pack due to continuous high-power discharge caused by range extender malfunctions or driver's continuous full-throttle high-power use. When the battery level is low, the method monitors the battery level, limits battery pack power generation, and provides timely warnings: real-time monitoring of battery level ensures the minimum battery usage level, preventing the battery pack from being unable to connect to high voltage and start the range extender due to extremely low battery level. Attached Figure Description

[0017] Figure 1 A flowchart illustrating the power-saving control method for a range-extended hybrid system provided in an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of a range-extended hybrid system provided in an embodiment of the present invention.

[0019] Figure 3 A flowchart illustrating the method for determining driving modes.

[0020] Figure 4 This is a schematic diagram illustrating the setting of multi-level power thresholds.

[0021] Figure 5 A flowchart illustrating the method for determining the battery power permissible state.

[0022] Figure 6 This is a flowchart illustrating the calculation of the required engine speed corresponding to the current accelerator pedal opening.

[0023] Figure 7 The flowchart shows the calculation process for the maximum rotational speed limit corresponding to the current maximum battery pack capacity.

[0024] Figure 8 The flowchart shows the calculation of the maximum speed limit corresponding to the currently available drive electric power.

[0025] Figure 9 This is a flowchart for calculating the actual electrical power of the drive motor.

[0026] Figure 10 Flowchart for calculating the power output requested by the range extender from the system.

[0027] Figure 11 This is a flowchart for calculating the available driving electrical power.

[0028] Figure 12 The flowchart shows the calculation of the maximum speed limit corresponding to the currently available drive electric power.

[0029] Figure 13 The flowchart shows the calculation process for the maximum speed limit of high-voltage accessory power.

[0030] Figure 14 This is a flowchart for calculating the actual power generation of the range extender. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0032] like Figure 1 As shown, in one embodiment of the present invention, a power-saving control method for a range-extended hybrid system is provided, comprising the following steps: S1. Real-time acquisition of system operating parameters, including real-time battery pack charge, motion mode calibration value, and driver power request signal; S2. Based on the real-time battery level, determine the driving mode and the battery power permissible state that the system should enter; S3. Based on the battery power permitting status, and in combination with the actual power generation of the range extender and the power consumption of the accessories, calculate the available drive power of the current system. S4. Based on the driver's power request signal, the required drive power or required speed is parsed out, and based on the available drive power and driving mode, the final allowable output limit of the drive motor is determined. S5. Output a control command to ensure that the actual output of the drive motor does not exceed the final allowable output limit. Specifically, obtain the system's maximum target speed based on the speed requirement and operating parameters corresponding to the current throttle (pedal) opening, and output the requested speed value for the drive motor.

[0033] In practical applications, such as Figure 2 As shown, the range-extended hybrid system is an integrated range-extending energy system, specifically including a high-voltage power energy unit, accessories (high-voltage accessory energy unit), and a low-voltage unit. The high-voltage power energy unit includes a range extender, a drive motor, and a battery pack; accessories include an air conditioning compressor and a step-down DC-DC converter; the low-voltage unit includes a PDU high-voltage distribution box, a 12V battery, function buttons, and throttle opening; the range extender includes an engine controller (ECU) and an ISG motor. This method can be used for range-extended hybrid motorboat systems in outdoor water sports. By configuring a range-extended motorboat system for outdoor water sports equipment, compared to a power generation system, the range-extending energy system operates within its optimal speed range, resulting in high efficiency and low emissions. It can also switch to pure electric mode, achieving zero emissions and low noise. Compared to pure electric power systems, this system saves on charging time and battery pack costs, while meeting the short-term, high-power demands of the motorboat's load equipment. Simultaneously, by acquiring the load's real-time power request, the battery pack and range extender work together to supply power, reducing system response time and improving the range and convenience of the extended-range motorboat system. Due to the low energy storage capacity of the battery pack, proper energy management and control can meet the driver's needs for short periods of high-speed, high-power driving. At low and medium speeds, the range extender promptly replenishes the battery pack, ensuring sufficient battery power and maximizing the driver's short-term high-speed driving experience.

[0034] Compared to pure electric power systems, this system saves on charging time and battery pack costs, while meeting the short-term, high-power demands of the motorboat's load equipment. Simultaneously, by acquiring the load's real-time power request, the battery pack and range extender work together to supply power, reducing system response time and improving the range and convenience of the extended-range motorboat system. Due to the low energy storage capacity of the battery pack, proper energy management and control can meet the driver's needs for short periods of high-speed, high-power driving. At low and medium speeds, the range extender promptly replenishes the battery pack, ensuring sufficient battery power and maximizing the driver's short-term high-speed driving experience.

[0035] In this embodiment of the invention, when the battery level is high, different driving modes are adjusted to reasonably protect and manage the system energy: for different operating conditions (long and short continuous full throttle high-power high-speed driving) and system states (three driving modes), the system actively identifies the operating conditions and limits the maximum speed of the drive motor to reasonably protect and manage the system energy, preventing the rapid power depletion and insufficient energy problem caused by the range extender malfunctioning or the driver continuously using full throttle high-power electricity due to continuous high-power discharge of the battery pack. When the battery power is low, monitor the battery power, limit the battery pack's power generation, and provide timely warnings: The battery pack can be a 2kW high-voltage battery pack, which monitors the battery power in real time, ensures the minimum battery power usage, prevents the battery pack from being unable to connect to high voltage and start the range extender due to extremely low power, and also prevents motorboats and other vehicles from being stranded in the lake due to power failure.

[0036] It should be noted that the power-saving control method provided in this embodiment of the invention can be applied not only to range-extended hybrid motorboats, but also to range-extended hybrid systems of vehicles such as range-extended hybrid motorcycles and range-extended hybrid cars.

[0037] In a preferred embodiment of the present invention, the engine controller is connected to the engine and is used to control the normal operation of the engine; wherein the ISG motor is the motor and the electronic control, and the motor drive shaft is connected to the engine flywheel disk through a spline, which can realize the functions of starting and stopping the engine, assisting the engine rotation and generating electricity; the speed of the drive motor of the range-extended hybrid system is reasonably controlled by the system controller (VCU) to provide power to the jet drive device of the motorboat.

[0038] The function buttons include the wake-up button (kl15), the high voltage button, and the start button. The kl15 button wakes up the VCU controller and automatically detects the low voltage. After the low voltage is successfully applied, the high voltage button requests the system to perform a self-test to apply high voltage. Once the system has applied high voltage, the start button requests the range extender to start and idles at low power to meet the power demand of the local load.

[0039] The battery pack is mainly used for engine starting, rapid response to short-term high power demands of the drive motor, and power compensation. The battery pack is usually kept between 50% and 80% charge to prevent the battery pack from being stored for a long time and then being used again with too low charge or insufficient power.

[0040] The system controller communicates with the ISG motor controller, drive motor controller, engine controller, battery pack controller, and high-voltage accessory (AC / DCDC) controller via a CAN bus; it is also connected to the function buttons and the high-voltage relays in the power distribution box via hard-wired I / O ports to coordinate and control the normal operation of the system.

[0041] The system controller analyzes the driver's required speed based on the obtained accelerator pedal opening. For different required speeds by the driver, it sets the system's maximum speed limit based on the current battery pack charge, system capacity, and driving mode, and finally outputs the requested speed value of the drive motor.

[0042] System energy includes the range extender's electrical power (generating power), the actual electrical power of the drive motor, the battery pack's charging / discharging power, and the power consumed by accessories (air conditioning power and step-down DC-DC power); the actual electrical power of the drive motor = torque * speed / 9550) / efficiency, and its calculation process is as follows: Figure 9 As shown; Based on the acquired battery pack charge and current load power, the system controller rationally controls the range extender to replenish the battery pack and supply power to the load, taking into account different power consumption and conditions. For example... Figure 10 As shown, the system requests the following calculation of the generator's power output: The system requests the range extender's generating power = requested battery pack charging power + current load power consumption; Current load power = Requested drive motor power consumption + (Air conditioner power + Step-down DC-DC power); The requested battery pack charging power is within the battery pack's allowable charging power range, based on the difference between the actual battery pack capacity and the target charging capacity (70%-80%). The larger the difference in capacity, the greater the requested battery pack charging power.

[0043] The system capability and driving mode settings define the system's maximum speed limit. System capability refers to the currently available drive electric power; the formula for calculating available drive electric power is as follows: Available driving power = battery pack discharge power + range extender actual power generation - power consumed by accessories (high-voltage accessory power). The specific calculation process is as follows: Figure 11 As shown; Battery pack discharge power = actual battery pack discharge power * attenuation factor. The specific calculation process is as follows: Figure 12 As shown; High-voltage accessory power (including air conditioner power and step-down DC-DC power) = (Actual air conditioner current * Actual air conditioner voltage + Actual step-down DC-DC current * Actual step-down DC-DC voltage) * 0.001. The specific calculation process is as follows: Figure 13 As shown; The actual power output of the range extender = voltage * current * 0.001. The specific calculation process is as follows: Figure 14 As shown.

[0044] like Figure 3 As shown, in a preferred embodiment of the present invention, the driving modes include a speed-limited power-saving mode, a full-speed mode, and a sport mode; the driving mode is determined by judging whether the real-time battery level is greater than the calibrated power-saving threshold. If the real-time power consumption is less than or equal to the calibrated power-saving threshold, the control system adopts a speed-limiting power-saving mode. If the real-time power consumption is greater than the calibrated power consumption threshold, determine whether the motion mode calibration value in the working parameters is set to 1: if the motion mode calibration value in the working parameters is set to 1, the control system adopts motion mode; if the motion mode calibration value in the working parameters is set to 0, the control system adopts full-speed mode.

[0045] Among them, the speed-limiting power-saving mode: when the battery is low, the system enters the speed-limiting power-saving mode and limits the speed to 5000 rpm. This can ensure that when the range extender generates full power, it can meet the load power of the drive motor and also provide appropriate power to the battery. Full Speed ​​Mode and Sport Mode: These modes primarily target different driving experiences. Full Speed ​​(6500 rpm) mode ensures a high-speed driving experience; however, because the battery pack discharges rapidly at 6500 rpm, the charge level briefly approaches the calibrated charge threshold, triggering a speed-limited charge-preserving mode that limits the speed to 5000 rpm. Sport Mode operates at the maximum speed limit corresponding to the current battery pack's highest charge level, ensuring a higher RPM (5000-6500 rpm) driving experience while extending the time spent maintaining a high-speed driving experience. For example, 40%-80% battery charge corresponds to a maximum RPM limit of 5000-6500 respectively. When the battery charge is 60%, the maximum RPM is limited to 5750 rpm for full-speed driving, extending the driving experience compared to Full Speed ​​(6500 rpm).

[0046] In a preferred embodiment of the present invention, the calibrated power reserve threshold is 40%-45%, which is used for power reserve when switching from speed-limited power reserve mode to full-speed mode or sport mode. 5% power reserve ensures a 10-second driving experience even in full-speed mode.

[0047] In a preferred embodiment of the present invention, the driving mode is full speed driving according to the maximum speed limit corresponding to the current maximum battery pack charge, wherein the initial value of the current maximum battery pack charge is 40%, the identification update condition 1 is that the throttle opening is less than or equal to 60% and the battery charge increases, the current maximum battery pack charge is equal to the actual charge, and when the identification update condition 1 is not met, the system retains the stored value of the previous moment. The second condition for identification and update is that the battery level gradually decreases to below the calibrated power reserve threshold of 40%, and the current maximum battery level is equal to 40% of the actual battery level. If the second condition for identification and update is not met, the system retains the stored value from the previous moment.

[0048] The purpose of identifying update condition 1 is to address unexpected acceleration due to a rise in battery power under full throttle. Specifically, when the current battery level is 39%, the maximum speed limit is 5000 RPM. If the driver continuously drives at full throttle for an extended period, in the system's speed-limited power-saving mode, the 5000 RPM limit ensures that the range extender can generate full power to both meet the drive motor's load and provide adequate battery charging. During this time, the battery level gradually increases. When the level reaches 45% or more, for example, 60%, the maximum speed limit is 5750 RPM. However, update condition 1 is not met, meaning the current maximum battery level is 40%. Only when the driver releases the accelerator—that is, the throttle opening is less than or equal to 60%—and then accelerates at full throttle again, will the current maximum battery level be updated to 60%, and the maximum speed limit be 5750 RPM.

[0049] In practical applications, the required engine speed corresponding to the current throttle (pedal) opening can be calculated using a linear lookup table (Tab_Curve1, a one-dimensional lookup table), as follows: Figure 6 As shown, input the current accelerator pedal opening and output the corresponding engine speed requirement.

[0050] The maximum speed limit corresponding to the current battery pack's highest charge level can be calculated using a linear lookup table (Tab_Curve2, a one-dimensional lookup table), as detailed below. Figure 7 As shown, input the initial value of the current battery pack's maximum charge, and output the corresponding maximum speed limit.

[0051] The system capability and driving mode settings define the system's maximum speed limit. The system capability, i.e., the maximum speed limit corresponding to the currently available drive electric power, can be calculated using a linear lookup table (Tab_Curve3, a one-dimensional lookup table), as detailed below. Figure 8 As shown, the input system can use driving electric power to output the corresponding maximum speed limit.

[0052] like Figure 4 and Figure 5 As shown, in a preferred embodiment of the present invention, the battery power permissible state is divided by a multi-level power threshold: If the real-time power level is greater than the first-level power threshold, the battery pack's discharge power will be used according to its actual capacity (i.e., the attenuation factor is 1). If the real-time power level is less than the threshold of the first level power level, the discharge power of the battery pack will be limited to 0kW (i.e., the attenuation factor is 0). If the real-time battery level is less than the threshold of the second-level battery level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging, indicating a first-level fault of low battery level. If the real-time battery level is less than the threshold of the third level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging. A low battery level level two fault will be indicated, and the device will be shut down. If the real-time battery level is less than the upper threshold of the fourth level, the discharge power of the battery pack will be limited to 0kW, and the charging gun will not be plugged in. A low battery level two fault will be indicated, and the device will be shut down.

[0053] In a preferred embodiment of the present invention, if the real-time power level is greater than the upper threshold of the fourth level power level, the discharge power of the battery pack is limited to 0 kW, and the range extender is not started or plugged in for charging. The system is then prompted with a low power level two fault and shut down. If the real-time battery level is greater than the upper threshold of the third level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging, indicating a first-level fault of low battery level. If the real-time power level is greater than the upper threshold of the second-level power level, the discharge power of the battery pack will be limited to 0kW; If the real-time battery level is greater than the first-level battery level threshold, the battery pack's discharge power will be used according to its actual capacity.

[0054] In a preferred embodiment of the present invention, based on the real-time power level, if the real-time power level is within the range of the upper threshold (e.g., 40%) and the lower threshold (e.g., 35%) of the first-level power level, then the real-time power level of the battery pack is determined as the first-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold (e.g., 32%) and lower threshold (e.g., 30%) of the second-level power level, then the real-time power level of the battery pack is determined to be the second-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold (e.g., 27%) and lower threshold (e.g., 25%) of the third-level power level, then the real-time power level of the battery pack is determined to be the third-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold (e.g., 22%) and lower threshold (e.g., 20%) of the fourth level power level, then the real-time power level of the battery pack is determined to be the fourth level power level. Wherein, the first level of power is greater than the second level of power, the second level of power is greater than the third level of power, and the third level of power is greater than the fourth level of power.

[0055] Furthermore, the power management of the range-extended hybrid system provided in this embodiment of the invention can be divided into the following multiple states: first level state, second level state, third level state, fourth level state; and fifth level state; The primary purpose of the first-level state is to ensure that when the system battery pack charge is greater than 40%, the battery energy can continuously discharge at high power and work together with the range extender to meet the driver's high-speed driving needs. The second-level state primarily aims to correct the system's battery pack discharge power by adjusting the attenuation factor from 0 to 1 based on battery pack charge levels of 35%-40%. The specific formula is as follows: Battery pack discharge power = actual battery pack discharge power * attenuation factor; By limiting the battery pack discharge power and limiting the drive motor speed, i.e. the load power consumption, the system electrical balance is achieved, i.e. the range extender's power generation equals the load power. The third level is mainly for situations such as: the range extender malfunctions and cannot start, or the range extender starts but the power generation is severely limited, the power balance cannot be maintained, the power continues to decrease, the low power warning is issued, and the system speed limit prompts the driver to return to the trip. The fourth level is primarily for situations where, during the return trip, the battery continues to decrease under system speed limits, the range extender is not activated or plugged into a charging port, and the system shuts down. In this stage, you can try to start the range extender while stationary or use slow charging to replenish the battery pack. The fifth level is mainly for the following situations: during the return trip, the system limits the speed and the range extender is activated, the battery level continues to drop, the charging gun is not plugged in, and the system shuts down and loses power; at this stage, the battery pack can only be recharged by slow charging.

[0056] In another embodiment of the present invention, a power-saving control device for a range-extended hybrid system is also provided, for implementing the above-described power-saving control method for a range-extended hybrid system, specifically including: The operating parameter acquisition module is used to acquire the operating parameters of the system in real time. The operating parameters include the real-time battery pack charge, the motion mode calibration value, and the driver's power request signal. The power analysis module is used to determine the driving mode and the battery power permissible state that the system should enter based on the real-time power level. The available drive power calculation module is used to calculate the available drive power of the current system based on the battery power permitting status and in combination with the actual power generated by the range extender and the power consumed by the accessories. The output upper limit determination module is used to parse the required drive power or required speed according to the driver's power request signal, and determine the final allowable output upper limit of the drive motor based on the available drive electric power and driving mode. The control command output module is used to output control commands to ensure that the actual output of the drive motor does not exceed the final allowable output limit.

[0057] It should be noted that each of the above modules can be implemented as a computer program, which can run on a computer device. The computer device's memory can store the computer program consisting of each module, enabling the processor to execute each step of the above method.

[0058] It should be understood that although the steps in the flowcharts of the embodiments of the present invention are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in each embodiment may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0059] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods.

[0060] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A power-saving control method for a range-extended hybrid system, the system comprising a range extender, a drive motor, a battery pack, and accessories, characterized in that, The power supply control method includes the following steps: The system acquires operating parameters in real time, including the real-time battery pack charge, motion mode calibration, and driver power request signal. Based on the real-time battery level, determine the driving mode and the battery power permissible state that the system should enter; Based on the battery power permitting status, and combined with the actual power generation of the range extender and the power consumption of the accessories, the available drive power of the current system is calculated. The required drive power or required speed is parsed from the driver's power request signal, and the final allowable output limit of the drive motor is determined based on the available drive power and driving mode. Output control commands to ensure that the actual output of the drive motor does not exceed the final allowable output limit; The driving modes include speed-limited battery protection mode, full-speed mode, and sport mode; the driving mode is determined by judging whether the real-time battery level is greater than the calibrated battery protection threshold. If the real-time power consumption is less than or equal to the calibrated power consumption threshold, the control system adopts a speed-limiting power consumption mode. If the real-time power consumption is greater than the calibrated power consumption threshold, determine whether the motion mode calibration value in the working parameters is set to 1: if the motion mode calibration value in the working parameters is set to 1, the control system adopts motion mode; if the motion mode calibration value in the working parameters is set to 0, the control system adopts full-speed mode. The calibrated power reserve threshold is 40%-45%, which is used for power reserve when switching from speed-limited power reserve mode to full-speed mode or sport mode. The driving mode is based on the maximum speed limit corresponding to the current maximum battery pack charge. The maximum speed limit corresponding to the current maximum battery pack charge is calculated by linear lookup table. The initial value of the current maximum battery pack charge is 40%. The identification update condition 1 is that when the throttle opening is less than or equal to 60% and the battery charge increases, when accelerating at full throttle again, the current maximum battery pack charge is equal to the actual charge. When the identification update condition 1 is not met, the system retains the stored value from the previous moment. The second condition for identification and update is that the battery level gradually decreases to below the calibrated power reserve threshold of 40%, and the current maximum battery level is equal to 40% of the actual battery level. If the second condition for identification and update is not met, the system retains the stored value from the previous moment.

2. The power-saving control method for a range-extended hybrid system according to claim 1, characterized in that, The accessories include an air conditioning compressor and a step-down DC-DC converter; the system also includes a low-pressure unit; the low-pressure unit includes a PDU high-voltage distribution box, a battery, function buttons, and a throttle opening; the range extender includes an engine controller and an ISG motor.

3. The power-saving control method for a range-extended hybrid system according to claim 1, characterized in that, The formula for calculating the available drive power is as follows: Available drive power = Discharge power of battery pack + Actual power generated by range extender - Power consumed by accessories.

4. The power-saving control method for a range-extended hybrid system according to claim 1, characterized in that, The battery power permissible state is divided by a multi-level power threshold: If the real-time power level is greater than the upper threshold of the first level power level, the discharge power of the battery pack will be used according to its actual capacity. If the real-time power level is less than the threshold value under the first level of power level, the discharge power of the battery pack will be limited to 0kW; If the real-time battery level is less than the threshold of the second-level battery level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging, indicating a first-level fault of low battery level. If the real-time battery level is less than the threshold of the third level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging. A low battery level level two fault will be indicated, and the device will be shut down. If the real-time battery level is less than the upper threshold of the fourth level, the discharge power of the battery pack will be limited to 0kW, and the charging gun will not be plugged in. A low battery level two fault will be indicated, and the device will be shut down.

5. The power-saving control method for a range-extended hybrid system according to claim 4, characterized in that, Also includes: If the real-time battery level is greater than the upper threshold of the fourth level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging. A low battery level level two fault will be indicated, and the device will be shut down and powered off. If the real-time battery level is greater than the upper threshold of the third level, the discharge power of the battery pack will be limited to 0kW, and the range extender will not be started or plugged in for charging, indicating a first-level fault of low battery level. If the real-time power level is greater than the upper threshold of the second-level power level, the discharge power of the battery pack will be limited to 0kW; If the real-time battery level is greater than the first-level battery level threshold, the battery pack's discharge power will be used according to its actual capacity.

6. The power-saving control method for a range-extended hybrid system according to claim 5, characterized in that, Also includes: Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the first-level power level, then the real-time power level of the battery pack is determined as the first-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the second-level power level, then the real-time power level of the battery pack is determined to be the second-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the third-level power level, then the real-time power level of the battery pack is determined to be the third-level power level. Based on the real-time power level, if the real-time power level is within the range of the upper threshold and lower threshold of the fourth level power level, then the real-time power level of the battery pack is determined to be the fourth level power level. Wherein, the first level of power is greater than the second level of power, the second level of power is greater than the third level of power, and the third level of power is greater than the fourth level of power.

7. A power-saving control device for a range-extended hybrid system, used to implement the power-saving control method for the range-extended hybrid system according to any one of claims 1-6, characterized in that, include: The operating parameter acquisition module is used to acquire the operating parameters of the system in real time. The operating parameters include the real-time battery pack charge, the motion mode calibration value, and the driver's power request signal. The power analysis module is used to determine the driving mode and the battery power permissible state that the system should enter based on the real-time power level. The available drive power calculation module is used to calculate the available drive power of the current system based on the battery power permitting status and in combination with the actual power generated by the range extender and the power consumed by the accessories. The output upper limit determination module is used to parse the required drive power or required speed according to the driver's power request signal, and determine the final allowable output upper limit of the drive motor based on the available drive electric power and driving mode. The control command output module is used to output control commands to ensure that the actual output of the drive motor does not exceed the final allowable output limit.

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