Multi-fixed-point power following control method and system for extended-range commercial vehicle

Abstract

The invention discloses a multi-fixed-point power following control method and system for an extended-range commercial vehicle, and the method comprises the steps: obtaining a pre-constructed multi-fixed-point efficient power set, collecting the operation state signal of the extended-range commercial vehicle in real time, and calculating the current required power of the whole vehicle based on the operation state signal; comparing the required power with each power set point in the multi-fixed-point high-efficiency power set, and selecting one power set point from the multi-fixed-point high-efficiency power set as target output power of the range extender according to a preset power switching strategy; the range extender is controlled to operate at the target output power, and meanwhile, the power battery is controlled to carry out charging and discharging compensation on the power difference between the target output power and the required power; according to the method, the range extender can run in the most efficient interval in most time, unnecessary start-stop and power fluctuation are reduced, the fuel economy is improved, meanwhile, the NVH performance of the whole vehicle is improved, and the service life of a power battery is prolonged.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle control technology, and in particular to a multi-fixed-point power following control method and system for range-extended commercial vehicles. Background Technology

[0002] Range-extended electric vehicles (REEVs), as a new energy vehicle technology that effectively alleviates range anxiety, have received widespread attention and application in the commercial vehicle sector. One of their core technologies lies in the Energy Management Strategy (EMS), which aims to achieve an optimal balance between vehicle performance and fuel economy by rationally allocating power between the range extender (APU) and the battery. Early energy management strategies often employed rule-based control methods, such as thermostat-based control strategies, which controlled the battery around a preset State of Charge (SOC) target value. When the battery SOC fell below a lower threshold, the range extender was activated and operated at a single fixed power until the SOC recovered to the upper threshold, at which point it shut down. This method is logically simple, easy to implement, and has certain utility under specific steady-state conditions. With the systematic development of control theory, some strategies based on instantaneous optimization and global optimization (such as dynamic programming algorithms) have been proposed. These methods aim to seek theoretically optimal fuel economy, providing a theoretical benchmark for the formulation of online strategies.

[0003] However, existing rule-based control strategies centered on single-point SOC anchoring typically suffer from the following problems when applied to commercial vehicles operating under complex and variable conditions: First, the load states (empty, half-loaded, fully loaded) and road conditions (urban congestion, suburban, highway cruising) of commercial vehicles vary greatly, causing the vehicle's power demand to fluctuate drastically over a wide range. A single fixed power output point cannot adaptively match the changing demands, often causing the range extender to deviate from its efficient operating range, leading to deterioration in fuel economy. Second, to maintain SOC stability, the range extender may need to frequently start and stop or make fine adjustments near the power point. This frequent switching of operating states not only causes vibration and noise in the vehicle's powertrain, significantly reducing ride comfort and NVH (Noise, Vibration, Harshness) performance, but the transient response lag of the range extender may also lead to insufficient power supply. Furthermore, when there is a large difference between the power demand and the fixed output power of the range extender, relying entirely on the power battery for high-rate charging and discharging compensation will exacerbate the electrochemical and thermal stress of the battery, leading to accelerated degradation of its cycle life and increasing the total life cycle cost of the vehicle.

[0004] Therefore, designing an energy management strategy that can balance fuel economy, smooth power response, and battery life has become a key technological bottleneck in the development of range-extended commercial vehicle technology. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] In view of the aforementioned existing problems, this invention is proposed. Therefore, this invention provides a multi-fixed-point power following control method for range-extended commercial vehicles to solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, the present invention provides a multi-fixed-point power following control method for range-extended commercial vehicles, comprising: Obtain a pre-constructed multi-fixed-point high-efficiency power set, which contains multiple discrete power setpoints corresponding to the high-efficiency operating range of the range extender; The system collects real-time operating status signals of the range-extended commercial vehicle and calculates the current power demand of the vehicle based on the operating status signals. The required power is compared with each power setpoint in the multi-fixed-point high-efficiency power set, and a power setpoint is selected from the multi-fixed-point high-efficiency power set as the target output power of the range extender according to the preset power switching strategy. The range extender is controlled to operate at the target output power, while the power battery is controlled to charge and discharge to compensate for the power difference between the target output power and the required power.

[0008] As a preferred embodiment of the multi-fixed-point power following control method for range-extended commercial vehicles described in this invention, the step of constructing the multi-fixed-point high-efficiency power set includes: A mathematical model is established with the total fuel consumption of the vehicle under typical cyclic operating conditions as the optimization objective; Under the constraints of vehicle power balance, range extender power output limit and power battery state of charge boundary, the mathematical model is solved by global optimization algorithm to obtain the optimal power control sequence covering the typical cyclic operating conditions. Cluster analysis is performed on the power values ​​in the optimal power control sequence to extract multiple regions where power values ​​are concentrated, and the representative power values ​​of each region are determined as discrete power setpoints of the multi-fixed-point high-efficiency power set.

[0009] As a preferred embodiment of the multi-fixed-point power following control method for range-extended commercial vehicles described in this invention, the step of selecting a power setpoint from the multi-fixed-point high-efficiency power setpoint as the target output power of the range extender according to a preset power switching strategy includes: When the required power is lower than the lowest power set point of the multi-point high-efficiency power collection and the state of charge of the power battery is higher than a preset pure electric drive threshold, the target output power is set to zero. When the required power is higher than the highest power set point of the multi-point high-efficiency power setpoint, the target output power is set to the maximum output power of the range extender.

[0010] As a preferred embodiment of the multi-fixed-point power following control method for range-extended commercial vehicles described in this invention, the power switching strategy is a hysteresis switching strategy, which includes: A power range band is preset for each power setpoint of the multi-point high-efficiency power concentration; When the required power is within the power range corresponding to a certain power setpoint, the power setpoint is selected as the target output power. When the required power exceeds the power range corresponding to the current power setpoint, and the excess state meets the preset duration or difference condition, the target output power is switched to another power setpoint.

[0011] As a preferred embodiment of the multi-fixed-point power following control method for range-extended commercial vehicles described in this invention, when the value of the required power is between two adjacent power setpoints in the multi-fixed-point high-efficiency power setpoint, the selection of the target output power is also determined based on the real-time state of charge of the power battery or the changing trend of the required power.

[0012] As a preferred embodiment of the multi-fixed-point power following control method for range-extended commercial vehicles described in this invention, the step of controlling the power battery to compensate for the power difference between the target output power and the required power includes: When the required power is greater than the target output power, the power battery is controlled to discharge in order to provide the power difference; When the required power is less than the target output power, the power battery is controlled to charge in order to absorb the power difference.

[0013] As a preferred embodiment of the multi-fixed-point power following control method for range-extended commercial vehicles described in this invention, the steps further include: The power of the charge-discharge compensation is adjusted according to the deviation between the real-time state of charge of the power battery and its preset target range.

[0014] Secondly, the present invention provides a multi-fixed-point power following control system for range-extended commercial vehicles, comprising: The data acquisition module is used to collect real-time operating status signals of range-extended commercial vehicles; The power decision module stores a multi-fixed-point high-efficiency power set containing multiple discrete power setpoints. The power decision module is configured to calculate the current power demand of the vehicle based on the operating status signal, compare the power demand with the multi-fixed-point high-efficiency power set, and select a power setpoint as the target output power of the range extender according to a preset power switching strategy. The power execution module is configured to control the operation of the range extender according to the target output power, and to control the power battery to charge and discharge to compensate for the power difference between the target output power and the required power.

[0015] As a preferred embodiment of the range-extended commercial vehicle multi-fixed-point power following control system described in this invention, the power decision module is further configured as follows: The target output power is selected using a hysteresis switching strategy. A power range band is set for each power setpoint, and the target output power is switched only when the required power exceeds the current power range band and a preset trigger condition is met.

[0016] As a preferred embodiment of the range-extended commercial vehicle multi-fixed-point power following control system described in this invention, the power decision module is further configured as follows: When selecting the target output power, the real-time state of charge of the power battery is used as one of the criteria for judgment.

[0017] Compared with existing technologies, the beneficial effects of the invention are as follows: 1. By pre-constructing multiple fixed-point high-efficiency power sets and controlling the range extender to follow these discrete power points online, this invention ensures that the range extender can operate in its most efficient range under most operating conditions, effectively avoiding the problem of the range extender frequently deviating from the high-efficiency range under the traditional single-point control strategy, thereby significantly improving the fuel economy of the whole vehicle under complex and variable operating conditions. 2. A hysteresis switching strategy with power range band and switching conditions is adopted, which effectively suppresses the frequent switching of the range extender's target power caused by small fluctuations in demand power, avoids unnecessary system vibration and noise, greatly improves the vehicle's NVH (noise, vibration and harshness) performance, and enhances the smoothness and comfort of the ride. 3. By controlling the power battery to dynamically compensate for the difference between the range extender's output power and the vehicle's required power, and by introducing an adjustment mechanism based on SOC deviation, this invention not only achieves a smooth response to the vehicle's power, but also actively manages the battery's state of charge, preventing it from being in an overcharged or over-discharged state for a long time, slowing down battery aging, extending the service life of the power battery, and reducing the vehicle's total life cycle cost. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a flowchart illustrating the overall process of a multi-fixed-point power following control method for range-extended commercial vehicles according to an embodiment of the present invention. Figure 2 This is a diagram showing the efficiency curve of the range extender system in the multi-fixed-point power following control method for range-extended commercial vehicles according to an embodiment of the present invention. Figure 3 This is an architecture diagram of a range-extended commercial vehicle multi-fixed-point power following control system according to an embodiment of the present invention. Detailed Implementation

[0019] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0022] This invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0023] Furthermore, in the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In addition, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] Example 1 Reference Figure 1 and Figure 2 This is the first embodiment of the present invention, which provides a multi-fixed-point power following control method for range-extended commercial vehicles, including: S1. Obtain a pre-built multi-fixed-point high-efficiency power set, which contains multiple discrete power setpoints corresponding to the high-efficiency operating range of the range extender. It should be noted that the purpose of this step is to pre-calculate and determine a set of discrete power points that enable the range extender to operate in the most efficient range for most of the time before the deployment of the vehicle control strategy. This set of power points is the basis for the subsequent online control strategy. Furthermore, an optimization mathematical model is established with the objective of minimizing the total fuel consumption of the vehicle under specific typical operating conditions. It should be noted that the specific typical cycle condition can be an industry standard condition, such as the China Heavy Commercial Vehicle Test Cycle (CHTC) or the World Light Vehicle Test Cycle (WLTC), or it can be a representative road spectrum collected and constructed based on actual vehicle operation data. Specifically, the objective function of this optimization model can be expressed as: in, This indicates the total fuel consumption during the entire operating cycle. and These represent the start and end times of the cyclic operation, respectively. Indicates at time The output power of the range extender (APU) is the control variable in this optimization model; This represents the instantaneous fuel consumption rate function of the range extender. This function model is typically obtained through bench testing calibration, and its data format can be found in [reference needed]. Figure 2 The efficiency curve of the range extender system is shown below; Furthermore, after defining the objective function of the optimization model, it is also necessary to set a series of constraints that conform to physical reality and control objectives for the above optimization model. These constraints mainly include the following: Vehicle power balance constraint: at any time The vehicle's drive system must meet the balance between the required power, the range extender's output power, and the power battery's output power. in, For the whole vehicle at all times The total power demand is calculated from vehicle speed, acceleration, road gradient, vehicle parameters, etc. For the power battery at all times The output power, a positive value indicates discharging, and a negative value indicates charging; Range extender power output constraint: The output power of the range extender cannot exceed its physical upper and lower limits. in, and These are the minimum and maximum stable output power of the range extender, respectively. State of Charge (SOC) Boundary Constraints for Power Batteries: To protect the battery and prevent overcharging and over-discharging, the SOC of the power battery must be maintained within a preset safe range. in, and These are the set lower and upper limits of SOC, respectively; Furthermore, the global optimization algorithm—Dynamic Programming (DP)—is used to solve the optimization model constructed above. Specifically, the dynamic programming algorithm solves the problem in reverse, starting from the end point of the working condition. Begin by iterating backwards to the starting point. For each discretized SOC state point at each time step, find an optimal range extender output power. This minimizes the cumulative fuel consumption (i.e., cost) from the point to the destination. By repeating this process, an optimal power control sequence covering the entire typical operating cycle can eventually be obtained. ; Furthermore, the optimal power control sequence obtained by the solution is... Perform data post-processing to extract discrete power setpoints; It should be noted that the solution of the present invention is achieved through... Statistical analysis of the data distribution revealed that the optimal range extender output power value is not uniformly distributed, but highly concentrated around several specific power values. These areas correspond to the high-efficiency operating range of the range extender. In response to this situation, the present invention uses the K-Means clustering algorithm to cluster all power values ​​in the optimal power control sequence. Specifically, all power values ​​are divided into a preset number (e.g., N) clusters, and the center point (or representative value such as mean or median) of each cluster is determined as a discrete power setpoint. These N power setpoints together constitute the required multi-fixed-point high-efficiency power set. This power set is stored in the vehicle controller or range extender controller for subsequent online power following control strategies to call upon. S2. Real-time acquisition of operating status signals of range-extended commercial vehicles, and calculation of the current power demand of the vehicle based on the operating status signals; It should be noted that this step is an online real-time calculation process aimed at determining the total power required by the vehicle at the current moment to maintain or change its motion state. It should be noted that the main body executing this step is the vehicle control unit (VCU), which obtains the operating status signals in real time from various sensors and sub-controllers (i.e., the perception layer of the present invention) through the vehicle communication network (such as CAN bus). Specifically, the real-time acquired operational status signals mainly include, but are not limited to: Driver intention signals: mainly obtained through the accelerator pedal position sensor, which shows the percentage of pedal opening, and through the brake pedal sensor, which shows the braking signal and braking depth. Vehicle dynamic signals: real-time vehicle speed obtained through a vehicle speed sensor, and real-time acceleration obtained through an acceleration sensor or by differentiating the vehicle speed signal; Vehicle environment and status signals: Road slope calculated by slope sensor or GPS altitude data, and real-time state of charge (SOC) of the power battery reported by the battery management system (BMS). Furthermore, after acquiring the aforementioned signals, the vehicle controller calculates the current power demand of the vehicle based on the vehicle dynamics model. The required power refers to the total power at the input of the transmission system needed to overcome all resistances encountered during vehicle operation and to achieve the acceleration desired by the driver. The processing steps for this vehicle dynamics model are as follows: First, calculate the total resistance of the vehicle. It is composed of rolling resistance air resistance Slope resistance and acceleration resistance It consists of four parts, and its mathematical expression is: Specifically, the formulas for calculating the resistance of each component in the total resistance are as follows: in, The total mass of the vehicle is expressed in kilograms (kg). For commercial vehicles, this value varies depending on the load condition (empty, half-loaded, fully loaded) and can be a preset typical value or estimated in real time by load sensors. The acceleration due to gravity is usually taken as 9.8 m / s². 2 ; Let be the rolling resistance coefficient of the tire, and be a dimensionless constant. The current road slope angle, in radians (rad), is obtained from slope sensors or GPS data. Let be the aerodynamic drag coefficient of the entire vehicle, and be a dimensionless constant. The frontal area of ​​a vehicle, expressed in square meters (m²). 2 ); Air density, expressed in kilograms per cubic meter (kg / m³) 3 ); For vehicles at any time The real-time speed, measured in meters per second (m / s), is provided by the vehicle speed sensor. For vehicles at any time Real-time acceleration, in meters per second. 2 It can be obtained by directly measuring the acceleration sensor or by calculating the derivative of the vehicle speed signal; This is the rotational mass conversion factor, used to account for the moment of inertia of rotating components of wheels and transmission systems. It is a dimensionless constant, typically ranging from 1.03 to 1.1. Secondly, calculate the total resistance. Then, the required power at the wheel ends of the vehicle can be obtained. : It should be noted that, considering the efficiency losses throughout the drivetrain from the power source (range extender and battery) to the wheels, the current total power demand of the vehicle is... The wheel power needs to be divided by the transmission system efficiency. ,get: in, The overall efficiency of the transmission system includes the efficiency of components such as the main reducer, differential, and half shaft. Its value can be an empirical constant or a function that varies with speed and load (stored in the controller in the form of a lookup table). Finally, through the above calculations, the vehicle controller is able to continuously calculate the real-time power demand of the vehicle. This value is used as the input for selecting the power target point; S3. Compare the required power with the power setpoints of the multi-point high-efficiency power setpoints, and select a power setpoint from the multi-point high-efficiency power setpoints as the target output power of the range extender according to the preset power switching strategy. It should be noted that this step is the core of the online control strategy. This step is executed in real time in the vehicle control unit (VCU) by receiving the calculated real-time power demand. As input, and utilizing the multi-fixed-point high-efficiency power set pre-built in S1 As a decision-making criterion, a specific target output power for the range extender is ultimately output. It should be noted that this decision-making process is not a simple numerical matching, but a preset power switching strategy with hysteresis characteristics, in order to balance fuel economy, system stability and driving experience. Furthermore, before performing the conventional power point selection, the system first assesses the extreme cases of power demand: Pure electric drive or low power operation condition determination: The system checks the current power demand. Is it below the minimum power setpoint of multi-point high-efficiency power concentration? At the same time, check the real-time state of charge of the power battery. Is it higher than a preset pure electric drive threshold? ; Specifically, if and This indicates that the vehicle's current power requirement is very small, and the battery has sufficient charge to drive the vehicle independently. In this case, to maximize energy efficiency and avoid the range extender operating in an inefficient region under extremely low load, the controller sets the target output power of the range extender to zero. The vehicle enters pure electric drive mode; Maximum power output determination: The system checks the current power demand. Does it exceed the highest power setpoint of the multi-point high-efficiency power collection? ; Specifically, if This indicates that the vehicle is under high-load conditions such as rapid acceleration or climbing hills with a full load, requiring the powertrain to provide maximum capacity. In this case, the controller directly sets the target output power of the range extender to the maximum stable output power that the range extender can achieve. ,Right now ; Furthermore, if the required power is at Within the normal range, the system starts the core power following and switching logic. In addition, in order to avoid the range extender frequently switching between different high efficiency points due to small fluctuations in power demand, thereby causing NVH problems and affecting system stability, the present invention adopts a hysteresis switching strategy, which is divided into setting power range band and power point holding and switching. Specifically, for a given power range, it is a multi-fixed-point high-efficiency power collection Each power setpoint A power range centered on this range can be defined as follows: in, and Power points The lower hysteresis width and the upper hysteresis width can be symmetrical or asymmetrically designed according to specific working conditions. Specifically, power point hold and switching can be further divided into the following sub-strategies: Maintain logic: Assume the current range extender is operating at the target power. Running, as long as the power demand is real time It always falls within the range corresponding to that power point, i.e. Then the controller will maintain the current target output power unchanged, that is Still ; Switching trigger logic: When real-time power demand... Exceeding the current power range, for example or If this happens, the system will not switch immediately, but will further determine whether the out-of-state condition meets the preset triggering conditions: Duration condition: The duration of the out-of-state condition exceeds a preset time threshold. ; Difference condition: The difference between the required power and the boundary value exceeds a preset power threshold. ; It should be noted that the controller only recognizes a real, continuous change in power demand when one of these triggering conditions is met, thereby triggering the target output power to shift to another adjacent, more suitable power setpoint (e.g., ...). or Switch to another device; Furthermore, when the power demand... The values ​​fall exactly at two adjacent power points. and When the hysteresis range band is between, that is Then the controller needs to make a better decision based on auxiliary information to determine whether to maintain the lower level. Or switch to a higher one in advance? The criteria for judgment at this time include: Based on the real-time state of charge (SOC) of the power battery: if If the value is below the center or lower limit of its target range, it indicates that the battery needs charging, and the controller tends to select a higher power setpoint. The goal is to replenish more battery power while meeting the required power output; if A value above the center or upper limit of its target range indicates sufficient battery power, and the controller tends to select a lower power setpoint. The goal is to allow the battery to discharge moderately in order to maintain a dynamic balance of SOC; Based on the trend of power demand changes: the rate of change of power demand can be obtained by differentiating or filtering the recent power demand series. ;like Furthermore, the trend is clear, indicating that the driver's intention is to accelerate or the vehicle is entering a high-load condition such as uphill driving, and the controller can predictively select a higher power setpoint. In order to respond to power demand in advance; conversely, if the trend is negative, a lower power setpoint is selected. ; It should be noted that, through the above strategy, the controller is able to select an optimal target output power for the range extender in each control cycle. ; S4. Control the range extender to operate at the target output power, and at the same time control the power battery to charge and discharge to compensate for the power difference between the target output power and the required power. It should be noted that this step translates the determined power distribution strategy into specific control commands for each component of the power system. This process is led by the vehicle control unit (VCU) and completed in collaboration with the range extender controller (APU Controller) and the battery management system (BMS). Specifically, this step can be divided into two parallel tasks: power control of the range extender and power compensation control of the power battery. Furthermore, in the power control task of the range extender, the vehicle control unit (VCU) is used to determine the target output power of the range extender. As a control command, the signal is sent to the range extender controller via the CAN bus. Upon receiving the command, the range extender controller executes its internal control algorithm, adjusting parameters such as the engine throttle opening, fuel injection quantity, and generator excitation current. This ensures that the actual output power of the range extender assembly (engine + generator) accurately tracks and stabilizes at a certain level. This ensures that the range extender always operates at the preset high-efficiency operating point; Furthermore, regarding the power compensation control task of the power battery, the core of this task is to accurately calculate and control the charging and discharging power of the power battery, and the steps are as follows: First, the vehicle controller calculates the vehicle's power demand at the current moment. With the target output power of the range extender The difference between the two is the base power that needs to be compensated by the power battery. : in, It is the vehicle's required power, calculated in real time. It is the target output power of the selected range extender. This is the basic compensation power that the power battery needs to provide; Specifically, when hour, A positive value indicates that the vehicle's power demand exceeds the power that the range extender can provide. In this case, it is necessary to control the discharge of the power battery to compensate for the power difference; when... hour, A negative value indicates that the power generated by the range extender exceeds the vehicle's demand. In this case, it is necessary to control the charging of the power battery to absorb this redundant power. Secondly, in order to achieve long-term stable control of the state of charge (SOC) of the power battery and prevent it from deviating from the healthy operating range, this invention also introduces a power adjustment term based on SOC deviation. This allows the system to adjust the power battery's power charge based on its real-time SOC and a preset target range (e.g., a range based on a predetermined target range). Centered on, with a width of The deviation within the specified range is used to correct the base compensation power, resulting in the final battery command power. It can be calculated using the following formula: in, This is the final command power sent to the battery management system (BMS). A positive value represents discharging, and a negative value represents charging. It is a corrected power term calculated based on the SOC deviation; It is the current state of charge of the power battery reported in real time by the BMS; It is the preset target SOC center value of the power battery (e.g., 60%). It is a proportional gain coefficient, the value of which is calibrated and determines the response strength of SOC adjustment, and this coefficient is positive; Specifically, when When this occurs, it indicates that the battery level is too high. Correction item If positive, the final command power A positive value will be subtracted from the base compensation power, meaning the battery is inclined to discharge more or charge less, in order to encourage the SOC to return to the target value; while when When this happens, it indicates that the battery level is low. Correction item Negative, final command power It will subtract a negative value from the base compensation power (i.e., add a positive value), which means it tends to charge the battery more or discharge less in order to improve the SOC; It should be noted that this processing method allows the power battery to not only act as a "buffer" for instantaneous power, but also achieve long-term dynamic balance of its state of charge through a negative feedback adjustment operation, effectively extending its service life. Ultimately, the vehicle controller only needs to apply the calculated battery command power... The signal is sent to the BMS, which then controls the power output module (such as the PCS) of the power battery to precisely execute the charging and discharging operations.

[0026] Example 2 Reference Figure 3 This is the second embodiment of the present invention, which provides a multi-fixed-point power following control system for range-extended commercial vehicles, including: The system is logically divided into a data acquisition module, a power decision module, and a power execution module. These modules interact at high speed through an in-vehicle communication network (such as a CAN bus) and work together to achieve optimized management of the vehicle's energy flow. Specifically, the system includes: Data Acquisition Module: This module physically corresponds to the perception layer. Its responsibility is to capture the complete operating status of the range-extended commercial vehicle in real time and accurately. This module consists of a series of sensors and sub-controllers distributed throughout the vehicle, mainly including: Accelerator pedal position sensor: used to detect the driver's acceleration intention; Vehicle speed sensor: used to obtain the real-time driving speed of the vehicle; Accelerometer / Gyroscope: Used to directly measure or assist in the calculation of real-time vehicle acceleration and road gradient; Battery Management System (BMS): Used to monitor and report various status parameters of the power battery in real time, the most important of which include real-time state of charge (SOC), terminal voltage, current, temperature, etc. In addition, the data acquisition module is not limited to other sensors and controllers, such as engine controllers and motor controllers. These sensors and controllers will send their own operating status information to the bus. Then, the data acquisition module will perform preliminary processing (such as filtering and unit conversion) on all the raw signals collected, and then broadcast them out through the CAN bus for use by the power decision module. Power Decision Module: This power decision module is the "brain" of the entire control system. Physically, it is usually integrated into the vehicle control unit (VCU) and corresponds to the decision layer. The core function of this module is to execute steps S2 and S3 as described in Example 1 above. The module internally contains key algorithms and data and is configured to perform the following operations: Storing multi-fixed-point high-efficiency power sets: The non-volatile memory of this module pre-stores multi-fixed-point high-efficiency power sets that are calculated and constructed offline in step S1. ; Calculate current power demand: This module receives real-time operating status signals from the data acquisition module and, based on the built-in vehicle dynamics model, calculates the precise power demand of the vehicle at the current moment. ; Based on the power switching strategy, the target output power is selected: This module is further configured as follows: Hysteresis switching strategy adopted: In order to achieve smooth control and avoid frequent start-stop of the range extender, this module strictly follows the hysteresis switching strategy for decision-making, that is, for each power setpoint of the multi-fixed-point high-efficiency power concentration. Set a power range band Furthermore, the power decision module only determines the required power when it detects the power demand. Only when the system stably and significantly (i.e., meets the preset duration or difference conditions) moves away from the range corresponding to the current target power point will a switch to an adjacent high-efficiency power point be triggered. This "unwavering" decision-making operation is the key to ensuring NVH performance and system stability. Integrating the real-time state of charge (SOC) of the power battery for decision-making: When there is ambiguity in the decision (for example, the required power is between the hysteresis range of two adjacent power setpoints), the power decision module will also use the real-time SOC of the power battery as a key auxiliary judgment criterion. The module will compare the real-time SOC reported by the BMS with the preset SOC target range. If the SOC is too low, the module will tend to select a higher power setpoint to use the surplus power to charge the battery; conversely, if the SOC is too high, it will tend to select a lower power setpoint to allow the battery to discharge moderately. Through this configuration operation, the power decision not only meets the instantaneous demand, but also serves the long-term energy balance of the entire vehicle. It should be noted that, through the above configuration, the power decision module can comprehensively consider fuel economy, power response, system stability, and battery health in each control cycle, and ultimately output an optimal target output power for the range extender. A battery command power after SOC deviation correction ; Power Execution Module: Physically corresponding to the execution layer, this module consists of execution components such as the range extender assembly (including its controller) and the power battery system (including the BMS and power converter). This module primarily receives control commands from the power decision module and is responsible for accurately translating them into physical actions. This module is configured as follows: The range extender controller operates based on the target output power: the range extender controller receives the target output power from the VCU. Upon receiving the command, the internal closed-loop control logic is immediately executed. By adjusting engine speed, load, and generator excitation, the actual output power of the range extender is quickly and stably reached and maintained at a certain level. ; Controlling the power battery to perform differential power charging and discharging compensation: The Battery Management System (BMS) receives the battery power command sent by the VCU. Then, a safety check is performed on the command (such as checking for over-temperature, over-current, over-pressure, etc.). After confirming safety, the power output / input module (such as a DC / DC converter or inverter) of the power battery is controlled to precisely execute the command. The size and direction of the discharge or charge are controlled to perfectly compensate for the dynamic difference between the vehicle's required power and the range extender's stable output power.

[0027] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0028] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0029] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0030] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0031] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0032] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A multi-fixed-point power following control method for range-extended commercial vehicles, characterized in that, include: Obtain a pre-constructed multi-fixed-point high-efficiency power set, which contains multiple discrete power setpoints corresponding to the high-efficiency operating range of the range extender; The system collects real-time operating status signals of the range-extended commercial vehicle and calculates the current power demand of the vehicle based on the operating status signals. The required power is compared with each power setpoint in the multi-fixed-point high-efficiency power set, and a power setpoint is selected from the multi-fixed-point high-efficiency power set as the target output power of the range extender according to the preset power switching strategy. The range extender is controlled to operate at the target output power, while the power battery is controlled to charge and discharge to compensate for the power difference between the target output power and the required power.

2. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 1, characterized in that, The steps for constructing the multi-fixed-point high-efficiency power set include: A mathematical model is established with the total fuel consumption of the vehicle under typical cyclic operating conditions as the optimization objective. Under the constraints of vehicle power balance, range extender power output limit and power battery state of charge boundary, the mathematical model is solved by global optimization algorithm to obtain the optimal power control sequence covering the typical cyclic operating conditions. Cluster analysis is performed on the power values ​​in the optimal power control sequence to extract multiple regions where power values ​​are concentrated, and the representative power values ​​of each region are determined as discrete power setpoints of the multi-fixed-point high-efficiency power set.

3. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 1, characterized in that, The step of selecting a power setpoint from the multi-point high-efficiency power setpoint as the target output power of the range extender according to the preset power switching strategy includes: When the required power is lower than the lowest power set point of the multi-point high-efficiency power collection and the state of charge of the power battery is higher than a preset pure electric drive threshold, the target output power is set to zero. When the required power is higher than the highest power set point of the multi-point high-efficiency power setpoint, the target output power is set to the maximum output power of the range extender.

4. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 1 or 3, characterized in that, The power switching strategy is a hysteresis switching strategy, which includes: A power range band is preset for each power setpoint of the multi-point high-efficiency power concentration; When the required power is within the power range corresponding to a certain power setpoint, the power setpoint is selected as the target output power. When the required power exceeds the power range corresponding to the current power setpoint, and the excess state meets the preset duration or difference condition, the target output power is switched to another power setpoint.

5. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 1, characterized in that, When the value of the required power is between two adjacent power setpoints of the multi-fixed-point high-efficiency power setpoint, the selection of the target output power is also determined based on the real-time state of charge of the power battery or the changing trend of the required power.

6. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 1, characterized in that, The step of controlling the power battery to compensate for the power difference between the target output power and the required power includes: When the required power is greater than the target output power, the power battery is controlled to discharge in order to provide the power difference; When the required power is less than the target output power, the power battery is controlled to charge in order to absorb the power difference.

7. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 6, characterized in that, The steps also include: The power of the charge-discharge compensation is adjusted according to the deviation between the real-time state of charge of the power battery and its preset target range.

8. A multi-fixed-point power following control system for range-extended commercial vehicles, characterized in that, include: The data acquisition module is used to collect real-time operating status signals of range-extended commercial vehicles; The power decision module stores a multi-fixed-point high-efficiency power set containing multiple discrete power setpoints. The power decision module is configured to calculate the current power demand of the vehicle based on the operating status signal, compare the power demand with the multi-fixed-point high-efficiency power set, and select a power setpoint as the target output power of the range extender according to a preset power switching strategy. The power execution module is configured to control the operation of the range extender according to the target output power, and to control the power battery to charge and discharge to compensate for the power difference between the target output power and the required power.

9. The multi-fixed-point power following control system for range-extended commercial vehicles as described in claim 8, characterized in that, The power decision module is also configured to: The target output power is selected using a hysteresis switching strategy. A power range band is set for each power setpoint, and the target output power is switched only when the required power exceeds the current power range band and a preset trigger condition is met.

10. The multi-fixed-point power following control method for range-extended commercial vehicles as described in claim 8 or 9, characterized in that, The power decision module is also configured to use the real-time state of charge of the power battery as one of the criteria when selecting the target output power.

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