Energy-saving vehicle-mounted generator and battery cooperative energy supply method

Abstract

The invention relates to the technical field of vehicle power systems, in particular to an energy-saving vehicle-mounted generator and battery cooperative energy supply method which is applied to a system comprising a first battery pack, a second battery pack, a vehicle-mounted generator, a driving motor, a vehicle control unit and a power divider. The method comprises the steps that a vehicle control unit obtains the vehicle state and the charge state of a double-battery pack in real time; during pure electric driving, the controller controls the double battery packs to jointly supply power according to the charge state proportion; when the charge state of any battery pack is lower than a threshold value, the controller generates a corresponding control instruction; when the vehicle brakes or slides, the controller controls the driving motor to recover energy, and distributes and stores electric energy to the battery pack; in the driving process, the instruction generation process, the energy recovery process and the power supply management process are executed circularly, so that the two battery packs alternately perform driving power supply and charging supplement, continuous energy supplement in the driving process is achieved, and the endurance and efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of vehicle power system technology, and in particular to an energy-saving method for coordinating power supply from an on-board generator and a battery. Background Technology

[0002] With the popularization of new energy vehicles, range-extended electric vehicles (REEVs) alleviate range anxiety to some extent by using an onboard generator to replenish the battery. However, current mainstream range-extending technologies typically employ a scheme where a single battery pack and an onboard generator work together. When the vehicle travels long distances and the battery charge drops to a low level, the generator needs to start charging the battery. During this process, because the battery pack simultaneously undertakes the dual tasks of driving the vehicle and receiving charging, the system is in a "charging and discharging" state. This not only leads to increased load on the battery cells, significant temperature rise, and reduced lifespan, but more importantly, the charging power is constrained by the driving power demand of the vehicle, resulting in a slow battery charge recovery rate and reduced overall vehicle energy efficiency. If users want to obtain good vehicle power while generating electricity, a more powerful generator must be equipped, which increases system cost, weight, and fuel consumption. Summary of the Invention

[0003] To overcome the above shortcomings, this invention provides an energy-saving method for coordinating the power supply of an on-board generator and a battery. This method aims to improve the technical problems of low operating efficiency, high battery loss, and limited charging speed in existing range-extended electric vehicles during long-distance driving, where a single power battery pack has to simultaneously undertake the tasks of driving and receiving charging.

[0004] In a first aspect, the present invention provides the following technical solution: an energy-saving vehicle-mounted generator and battery coordinated power supply method, the method being applied to a coordinated power supply system, the coordinated power supply system including a first battery pack, a second battery pack, a vehicle-mounted generator, a drive motor, a vehicle controller, and a power distributor, the method comprising the following steps:

[0005] The vehicle controller acquires vehicle status information and the state of charge of the first and second battery packs in real time.

[0006] When the vehicle is in pure electric drive mode powered by the battery pack drive motor, the vehicle controller controls the power divider to make the first battery pack and the second battery pack jointly power the drive motor according to the state of charge of the first battery pack and the second battery pack.

[0007] The vehicle controller makes a judgment based on the real-time acquired state of charge. If it is determined that the state of charge of the first battery pack is lower than a preset low charge threshold, a first control command is generated. If it is determined that the state of charge of the second battery pack is lower than the low charge threshold, a second control command is generated.

[0008] When the vehicle is braking or coasting, the vehicle controller controls the drive motor to operate in energy recovery mode and delivers the generated regenerated electrical energy to the first battery pack and / or the second battery pack for storage through the power distributor;

[0009] During vehicle operation, the system cyclically executes control command generation, energy recovery, and corresponding power supply management processes based on the state of charge, enabling the first battery pack and the second battery pack to alternately provide power for driving and charging.

[0010] Preferably, the process of acquiring vehicle status information and the state of charge of the first battery pack and the second battery pack in real time through the vehicle controller includes:

[0011] The vehicle controller periodically reads and parses vehicle speed signal messages (representing vehicle speed) and demand torque messages (representing driving requirements) through the vehicle CAN network.

[0012] The vehicle controller calculates the real-time power demand of the vehicle based on the demand torque message and the current vehicle speed.

[0013] The vehicle controller obtains the real-time voltage, real-time current and real-time temperature of the first battery pack and the second battery pack respectively;

[0014] The vehicle controller calculates the real-time state of charge of the first battery pack based on the real-time voltage, real-time current and real-time temperature of the first battery pack.

[0015] The vehicle controller calculates the real-time state of charge of the second battery pack based on the real-time voltage, real-time current and real-time temperature of the second battery pack.

[0016] Preferably, the process in which the first battery pack and the second battery pack jointly supply power to the drive motor according to a preset power distribution ratio includes:

[0017] The vehicle controller compares the real-time state of charge of the first battery pack with the real-time state of charge of the second battery pack.

[0018] The vehicle controller calculates the first target output power of the first battery pack and the second target output power of the second battery pack based on the comparison results and the preset state of charge balance strategy, wherein the sum of the first target output power and the second target output power is equal to the real-time power demand of the vehicle.

[0019] The vehicle controller converts the first target output power and the second target output power into control signals for the first power adjustment module and the second power adjustment module in the power distributor, respectively.

[0020] The power distributor responds to the control signal by controlling the output power from the first battery pack through the first power adjustment module and controlling the output power from the second battery pack through the second power adjustment module, so that the first battery pack and the second battery pack jointly supply power to the drive motor at the first target output power and the second target output power.

[0021] Preferably, the process by which the vehicle controller converts the first target output power and the second target output power into control signals for the first power adjustment module and the second power adjustment module in the power distributor includes:

[0022] The vehicle controller calculates the first target current value or first duty cycle signal required by the first power adjustment module based on the first target output power and the real-time voltage of the first battery pack.

[0023] The vehicle controller calculates the second target current value or second duty cycle signal required by the second power regulation module based on the second target output power and the real-time voltage of the second battery pack.

[0024] The vehicle controller sends a first drive command containing the first target current value or the first duty cycle signal to the first power regulation module through the first control channel;

[0025] The vehicle controller sends a second drive command, which includes the second target current value or the second duty cycle signal, to the second power regulation module through the second control channel.

[0026] Preferably, the workflow of the first power regulation module and the second power regulation module includes:

[0027] In response to the received first drive command, the first power regulation module adjusts the conduction state or equivalent impedance of its switching device so that the current flowing through the first power regulation module matches the first target current value, or makes the pulse width of its output voltage correspond to the first duty cycle signal.

[0028] In response to the received second drive command, the second power regulation module adjusts the conduction state or equivalent impedance of its switching device so that the current flowing through the second power regulation module matches the second target current value, or makes the pulse width of its output voltage correspond to the second duty cycle signal.

[0029] The adjusted output current of the first battery pack and the output current of the second battery pack are combined at the power junction point of the power divider to jointly provide a total drive current to the input terminal of the drive motor.

[0030] Preferably, the generation process of the first control command and the second control command includes:

[0031] The vehicle controller compares the real-time state of charge of the first battery pack with a preset first low charge threshold.

[0032] If the real-time state of charge of the first battery pack is lower than the first low charge threshold, the vehicle controller generates a first control command that includes starting the on-board generator, charging the first battery pack, and isolating the first battery pack from the drive circuit.

[0033] The vehicle controller compares the real-time state of charge of the second battery pack with a preset second low charge threshold.

[0034] If the real-time state of charge of the second battery pack is lower than the second low charge threshold, the vehicle controller generates a second control command that includes starting the on-board generator, charging the second battery pack, and isolating the second battery pack from the drive circuit.

[0035] Preferably, when the vehicle is in a braking or coasting state, the process by which the vehicle controller controls the drive motor to operate in energy recovery mode includes:

[0036] When the vehicle controller detects that the brake pedal signal is triggered or the vehicle power demand is negative, it determines that the vehicle is in a braking or coasting state.

[0037] The vehicle controller sends a mode switching command to the controller of the drive motor to control the drive motor to switch from driving mode to power generation mode;

[0038] In power generation mode, the drive motor converts the vehicle's kinetic energy into three-phase alternating current, which is then rectified by the motor controller and output as DC regenerated power to the input of the power distributor.

[0039] The vehicle controller determines the allocation ratio of regenerative energy based on the real-time state of charge of the first battery pack and the second battery pack, and generates a corresponding charging allocation command to send to the power distributor.

[0040] In response to the charging distribution command, the power distributor delivers the received regenerated electrical energy to the first battery pack and / or the second battery pack respectively for charging and storage according to the distribution ratio.

[0041] Preferably, the process of the vehicle controller sending a mode switching command to the controller of the drive motor to control the drive motor to switch from drive mode to generator mode includes:

[0042] The vehicle controller generates a mode switching instruction message containing a target operating mode identifier and a target generated torque value;

[0043] The vehicle controller sends the mode switching command message to the drive motor controller via the vehicle control CAN bus;

[0044] The controller of the drive motor receives and parses the mode switching instruction message to obtain the target operating mode identifier and the target power generation torque value;

[0045] The controller of the drive motor switches the control logic of its internal inverter from motor torque control to generator torque control according to the target operating mode identifier.

[0046] The controller of the drive motor adjusts the pulse width modulation signal of the power switching device in the inverter according to the target generating torque value, so that the drive motor generates a braking torque corresponding to the target generating torque value and outputs three-phase AC power.

[0047] Preferably, the process of cyclically executing control command generation, energy recovery, and corresponding power supply management based on the state of charge includes:

[0048] When the state of charge of both the first battery pack and the second battery pack is higher than a preset low charge threshold, the first battery pack and the second battery pack are controlled to jointly supply power to the drive motor.

[0049] During the period when the first battery pack and the second battery pack are jointly powered, when the state of charge of the first battery pack drops below a preset low charge threshold, the on-board generator is started to charge the first battery pack, and the second battery pack is controlled to supply power to the drive motor alone.

[0050] While the second battery pack is supplying power to the drive motor alone and the first battery pack is being charged by the vehicle generator, when the state of charge of the second battery pack drops below a preset low charge threshold, the vehicle generator is switched to charge the second battery pack, and the first battery pack is controlled to supply power to the drive motor alone.

[0051] During continuous vehicle operation, based on the changes in the state of charge of the first battery pack and the second battery pack, the process of switching from the common power supply state, through the charging state of the first battery pack and the independent power supply state of the second battery pack, to the charging state of the second battery pack and the independent power supply state of the first battery pack is continuously executed, thereby alternating the roles of the first battery pack and the second battery pack between driving power supply and charging replenishment.

[0052] The present invention has the following beneficial effects:

[0053] 1. In this invention, by physically isolating and dynamically alternating the first and second battery packs in terms of power supply and charging roles, each battery pack undertakes only a single task during operation. This avoids the problems of complex energy conversion links, increased internal losses, increased battery temperature, and reduced cycle life caused by charging while driving in traditional single-battery-pack solutions. The generator can stably charge the isolated battery pack in the most efficient power range without being disturbed by drive power demand, thereby optimizing the energy utilization efficiency of the entire system.

[0054] 2. In this invention, the dual battery pack configuration itself constitutes a backup energy system. Even if one battery pack fails due to a fault or complete discharge, the other battery pack can still independently provide driving force. Together with the on-board generator, it can ensure that the vehicle can continue to drive to a safe location. This redundancy design significantly improves the reliability and safety of the vehicle under long-distance or extreme conditions and reduces the risk of the vehicle breaking down due to a single point of failure in the battery system.

[0055] 3. In this invention, during regenerative braking, the vehicle controller can intelligently allocate the regenerated energy to the battery pack with lower charge or stronger charging acceptance based on the real-time state of charge of the two battery packs. This state-based intelligent allocation strategy, compared to a single battery pack system, can more fully and safely absorb regenerated braking energy, further improving the vehicle's energy efficiency and extending its driving range. Attached Figure Description

[0056] Figure 1 This is a schematic flowchart of an energy-saving vehicle-mounted generator and battery co-powering method proposed in this invention. Detailed Implementation

[0057] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] In a first embodiment of the present invention, the present invention provides a method for energy-saving vehicle-mounted generators and batteries to work together for power supply, such as... Figure 1 As shown, the method is applied to a collaborative power supply system, which includes a first battery pack, a second battery pack, an on-board generator, a drive motor, a vehicle controller, and a power distributor. The method includes the following steps:

[0059] The vehicle controller obtains real-time vehicle status information and the state of charge of the first and second battery packs.

[0060] Furthermore, the process of acquiring vehicle status information and the state of charge of the first and second battery packs in real time through the vehicle controller includes:

[0061] The vehicle controller periodically reads and parses vehicle speed signal messages, which represent vehicle speed, and demand torque messages, which represent driving needs, through the vehicle's CAN network.

[0062] The vehicle controller calculates the real-time power demand of the vehicle based on the demand torque message and the current vehicle speed.

[0063] The vehicle controller obtains the real-time voltage, real-time current and real-time temperature of the first battery pack and the second battery pack respectively;

[0064] The vehicle controller calculates the real-time state of charge of the first battery pack based on the real-time voltage, real-time current and real-time temperature of the first battery pack.

[0065] The vehicle controller calculates the real-time state of charge of the second battery pack based on its real-time voltage, real-time current, and real-time temperature.

[0066] Specifically, firstly, the vehicle controller connects to the vehicle controller area network (CAN network) and actively reads and parses specific messages broadcast on the network at fixed intervals, such as every 10 milliseconds. The key messages that must be read include at least: a vehicle speed signal message provided by the vehicle controller or gateway, representing the current actual driving speed; and a torque demand message generated by driver operation or advanced driver assistance systems, representing the vehicle's current driving needs. The vehicle controller extracts the vehicle speed and torque demand values ​​from specific data bits in these messages. Then, based on the acquired current vehicle speed and torque demand values, the vehicle controller calculates the vehicle's real-time power demand according to vehicle dynamics principles. The formula for calculating this real-time power demand is as follows:

[0067]

[0068] Among them, P req This indicates real-time power demand, expressed in kilowatts (T). req The required torque is expressed in Newton-meters (N·m), and n represents the real-time speed of the drive motor. This speed can be calculated based on the current vehicle speed and the fixed transmission ratio of the vehicle's transmission system, and is expressed in revolutions per minute (rpm). The real-time required power is the basic parameter for subsequent energy allocation decisions.

[0069] Simultaneously, the vehicle controller sends data request commands to the first battery management unit in the first battery pack and the second battery management unit in the second battery pack via its dedicated battery management communication channel, such as another CAN bus or daisy-chain communication, or passively receives the status data reported by them periodically. It obtains the real-time total voltage, real-time total current, and temperature sampling values ​​representing the cell temperature of the first battery pack from the first battery management unit. Similarly, it obtains the real-time total voltage, real-time total current, and temperature sampling values ​​of the second battery pack from the second battery management unit. Then, the vehicle controller inputs the real-time voltage, current, and temperature data of the first battery pack into its internally running first battery state estimation algorithm model. The core of this model uses the ampere-hour integration method combined with the open-circuit voltage correction method for state of charge estimation. The specific calculation steps are as follows:

[0070] The first step is to calculate the preliminary state of charge (SOC) using the ampere-hour integral method. AH :

[0071]

[0072] Where SOC(t0) is the initial state of charge, C N The rated capacity of the battery pack is given in ampere-hours (AH), I(τ) is the real-time current (positive during charging and negative during discharging), and η is the coulomb efficiency factor.

[0073] The second step involves introducing a correction based on open-circuit voltage. When the battery is at rest or operating under low current conditions, the vehicle controller uses real-time voltage to look up the pre-calibrated open-circuit voltage versus state of charge (SOC) curve. ocv (U), to obtain a reference state of charge value;

[0074] The third step is to obtain the SOC from the ampere-hour integration method using Kalman filtering or a proportional-integral algorithm. AH SOC obtained by the open-circuit voltage method ocv Data fusion is performed to ultimately output the high-precision real-time state of charge (SOC1) value of the first battery pack.

[0075] Using the exact same estimation model and calculation steps, the vehicle controller calculates and outputs the real-time state of charge (SOC2) value of the second battery pack based on the real-time voltage, current, and temperature data of the second battery pack. Through the above process, the vehicle controller completes comprehensive and periodic monitoring of the vehicle's driving status and the energy status of the two independent energy carriers, providing accurate data input for subsequent intelligent decision-making. All acquired and calculated data are stored in the random access memory of the vehicle controller for subsequent steps to access.

[0076] When the vehicle is in pure electric drive mode powered by the battery pack drive motor, the vehicle controller controls the power divider to make the first and second battery packs jointly supply power to the drive motor according to a preset power distribution ratio, based on the state of charge of the first and second battery packs.

[0077] Furthermore, the process of the first battery pack and the second battery pack jointly supplying power to the drive motor according to a preset power allocation ratio includes:

[0078] The vehicle controller compares the real-time state of charge of the first battery pack with the real-time state of charge of the second battery pack.

[0079] Based on the comparison results and the preset state of charge balance strategy, the vehicle controller calculates the first target output power of the first battery pack and the second target output power of the second battery pack, wherein the sum of the first target output power and the second target output power is equal to the real-time power demand of the vehicle.

[0080] The vehicle controller converts the first target output power and the second target output power into control signals for the first power adjustment module and the second power adjustment module in the power distributor, respectively.

[0081] The power distributor responds to the control signal by controlling the output power from the first battery pack through the first power regulation module and controlling the output power from the second battery pack through the second power regulation module, so that the first battery pack and the second battery pack jointly supply power to the drive motor with the first target output power and the second target output power.

[0082] Furthermore, the process by which the vehicle controller converts the first target output power and the second target output power into control signals for the first power adjustment module and the second power adjustment module in the power distributor, respectively, includes:

[0083] The vehicle controller calculates the first target current value or first duty cycle signal required by the first power regulation module based on the first target output power and the real-time voltage of the first battery pack.

[0084] The vehicle controller calculates the second target current value or second duty cycle signal required by the second power regulation module based on the second target output power and the real-time voltage of the second battery pack.

[0085] The vehicle controller sends a first drive command containing a first target current value or a first duty cycle signal to the first power regulation module through the first control channel;

[0086] The vehicle controller sends a second drive command, which includes a second target current value or a second duty cycle signal, to the second power regulation module through the second control channel.

[0087] Furthermore, the workflow of the first power regulation module and the second power regulation module includes:

[0088] In response to the received first drive command, the first power regulation module adjusts the conduction state or equivalent impedance of its switching device so that the current flowing through the first power regulation module matches the first target current value, or makes the pulse width of its output voltage correspond to the first duty cycle signal.

[0089] In response to the received second drive command, the second power regulation module adjusts the conduction state or equivalent impedance of its switching device so that the current flowing through the second power regulation module matches the second target current value, or makes the pulse width of its output voltage correspond to the second duty cycle signal.

[0090] The adjusted output current of the first battery pack and the output current of the second battery pack are combined at the power junction point of the power divider to jointly provide the total drive current to the input terminal of the drive motor.

[0091] Specifically, the vehicle controller first calculates the difference in state of charge between the two battery packs, that is:

[0092] ΔSOC=SOC1-SOC2;

[0093] Wherein, SOC1 is the real-time state of charge of the first battery pack, and SOC2 is the real-time state of charge of the second battery pack.

[0094] The preset state-of-charge (SOC) balancing strategy aims to bring the SOC of the two battery packs into equilibrium. Based on this strategy, the vehicle controller determines the SOC difference (ΔSOC) and the real-time power demand (P). req Calculate the first target output power P allocated to the first battery pack. bat1_target The second target output power P of the second battery pack bat2_target ;

[0095] One specific implementation method uses a proportional allocation algorithm, and the calculation formula is as follows:

[0096] P bat1_target =P req ×k1;

[0097] P bat2_target =P req ×k2;

[0098] Where k1 and k2 are dynamic allocation coefficients, and satisfy k1 + k2 = 1. The allocation coefficients are determined by the following rules:

[0099] When ΔSOC≥ΔSOC deadband When the (positive dead zone threshold) is reached, it indicates that the state of charge (SOC) of the first battery pack is significantly higher than that of the second battery pack. Therefore, k1 = 0.7 and k2 = 0.3 are set, meaning the battery pack with the higher SOC will handle more power output. When ΔSOC ≤ -ΔSOC deadband When the (negative dead zone threshold) is reached, it indicates that the state of charge of the second battery pack is significantly higher than that of the first battery pack. Therefore, k1 = 0.3 and k2 = 0.7 are set.

[0100] When -ΔSOC deadband <ΔSOC<ΔSOC deadband When this indicates that the states of charge of the two are basically in equilibrium, we set k1 = 0.5 and k2 = 0.5, where ΔSOC deadband The preset dead zone threshold is set, for example, to 5%. The calculation must ensure that P... bat1_target +P bat2_target =P req ;

[0101] The vehicle controller obtains the real-time voltage U of the first battery pack. bat1 Real-time voltage U of the second battery pack bat2 For the first power regulation module, the vehicle controller determines the first target output power P. bat1_target and the voltage U of the first battery pack bat1 Calculate its first target current value I target1 :

[0102]

[0103] If the first power regulation module adopts PWM control, then based on the target current value and the module's current control loop algorithm, such as a PI controller, the required first duty cycle signal Duty1 is calculated. The discrete form of the PI control algorithm is as follows:

[0104]

[0105] Among them, e I (k)=I target1 -I actual1 (k) represents the current error in the k-th control cycle, I actual1 (k) represents the real-time sampled output current of the first battery pack, K p and K i For proportional and integral coefficients;

[0106] The same calculation logic is used for the second power regulation module:

[0107]

[0108] The second duty cycle signal, Duty2, is calculated. Subsequently, the vehicle controller sends a first drive command to the first power regulation module through its dedicated first control channel, such as a PWM output port or a first SPI communication channel. This command data frame contains the calculated first target current value I. target1 Alternatively, the first duty cycle signal Duty1 is sent to the second power regulation module via an independent second control channel, containing I... target2 Or the second drive command of Duty2;

[0109] After receiving the first drive command, if the command is a target current value, the first power regulation module's internal current closed-loop controller will sample the current I flowing through the module in real time. actual1 and with I target1 By adjusting the duty cycle of the gate drive signal of its main switching device, such as an IGBT or MOSFET, the conduction state is changed, thereby dynamically adjusting the equivalent impedance of the module to make I... actual1 Quick Tracking I target1 If the instruction is the duty cycle signal Duty1, the module directly drives the switching device according to the signal to generate an output voltage with the corresponding pulse width.

[0110] The second power regulation module operates in the same manner, controlling its output current I. actual2 Tracking I target2 Alternatively, based on the voltage output from Duty2, the controlled current I from the first battery pack, after precise adjustment, can be... actual1 With the controlled current I from the second battery pack actual2The currents are guided to a common conductive bus inside the power divider, i.e., the power convergence point. The two currents are superimposed here to form the total drive current I. total :

[0111] I total =I actual1 +I actual2 ;

[0112] The total drive current is directly supplied to the controller input of the drive motor to drive its operation, thus enabling the first and second battery packs to jointly power the system according to a preset strategy. The busbar in the power divider is typically composed of a low-impedance copper bus or busbar to ensure minimal voltage drop at the current convergence point. This process is re-executed every control cycle, for example, 1 millisecond, thereby achieving dynamic, state-of-charge-based dual-battery pack power coordination output.

[0113] The vehicle controller makes a judgment based on the real-time acquired state of charge. If it determines that the state of charge of the first battery pack is lower than the preset low charge threshold, it generates a first control command. If it determines that the state of charge of the second battery pack is lower than the low charge threshold, it generates a second control command.

[0114] Furthermore, the generation process of the first control command and the second control command includes:

[0115] The vehicle controller compares the real-time state of charge of the first battery pack with a preset first low charge threshold.

[0116] If the real-time state of charge of the first battery pack is lower than the first low charge threshold, the vehicle controller generates a first control command that includes starting the on-board generator, charging the first battery pack, and isolating the first battery pack from the drive circuit.

[0117] The vehicle controller compares the real-time state of charge of the second battery pack with a preset second low charge threshold.

[0118] If the real-time state of charge of the second battery pack is lower than the second low charge threshold, the vehicle controller generates a second control command that includes starting the on-board generator, charging the second battery pack, and isolating the second battery pack from the drive circuit.

[0119] Specifically, the vehicle controller reads the preset first low battery threshold (SOC). L1 This threshold is a safety lower limit set to protect the first battery pack. It is usually set between 20% and 25% based on the battery's chemical characteristics. For example, if it is set to 20%, the vehicle controller performs a numerical comparison and judgment. If the condition SOC1 < SOC is met... L1If the first battery pack's state of charge is determined to be below a preset low charge threshold, the vehicle controller immediately generates a first control command. This command is a structured data object or a predefined command frame, and its specific operation content is as follows: First, start the on-board generator, instructing the generator controller to start the internal combustion engine and make it run at a preset high-efficiency power generation speed point; second, charge the first battery pack, instructing the power distributor to route the output power of the on-board generator to the charging input terminal of the first battery pack and manage the charging according to the preset charging curve; third, isolate the first battery pack from the drive circuit, instructing the power distributor to disconnect or lock the main power supply path between the first battery pack and the drive motor to ensure that the first battery pack no longer undertakes the drive discharge task during charging. After the first control command is generated, it is stored in the command buffer of the vehicle controller and waits to be sent to the relevant execution components.

[0120] Within the same control cycle, the vehicle controller performs judgments on the second battery pack in parallel or sequentially, and the controller reads the preset second low charge threshold (SOC). L2 Second Low Battery Threshold (SOC) L2 Can be compared with the first low power threshold SOC L1 The values ​​can be the same, for example, all set to 20%, or they can be set to different values ​​depending on the system optimization strategy, such as setting the SOC... L2 The value is set to 22% to achieve peak-shaving triggering. The vehicle controller performs a numerical comparison and judgment. If the condition SOC2 < SOC is met, the system will determine the triggering method. L2 If the condition is met, the second battery pack's state of charge is determined to be below the preset low charge threshold. When the above condition is met, the vehicle controller immediately generates a second control command. This command is also a structured data object, and its specific operation content is as follows: First, start the on-board generator, instructing the generator controller to control the internal combustion engine to start and run it at the preset high-efficiency power generation speed point; second, charge the second battery pack, instructing the power distributor to route the output power of the on-board generator to the charging input terminal of the second battery pack; third, isolate the second battery pack from the drive circuit, instructing the power distributor to disconnect or lock the main power supply path between the second battery pack and the drive motor. After the second control command is generated, it is also stored in the vehicle controller's command cache area.

[0121] Since the system is designed to charge only one battery pack at a time, if a second control command is generated before the first control command has been completed, or if two conditions are theoretically met simultaneously, the vehicle controller's arbitration logic will ensure that only one charging command is executed. A preferred arbitration strategy is based on time sequence or priority. For example, the rule can be set such that when the first control command has been generated and is being executed, the newly generated second control command is ignored until the first battery pack is charged to a certain exit threshold, at which point the first control command is cleared, and the system responds to the second control command. If the two conditions are triggered almost simultaneously, the first battery pack can be given higher priority for charging. After arbitration, the selected valid control command will be sent to the on-board generator controller and power distributor through the corresponding communication channel to trigger subsequent physical execution actions. This judgment and command generation process is repeated in each control cycle, thereby achieving continuous monitoring and intelligent decision-making of the energy status of the two battery packs.

[0122] When the vehicle is braking or coasting, the vehicle controller controls the drive motor to operate in energy recovery mode and delivers the generated regenerated electrical energy to the first battery pack and / or the second battery pack for storage through the power distributor.

[0123] Furthermore, when the vehicle is braking or coasting, the process by which the vehicle controller controls the drive motor to operate in energy recovery mode includes:

[0124] When the vehicle controller detects that the brake pedal signal has been triggered or the vehicle power demand is negative, it determines that the vehicle is in a braking or coasting state.

[0125] The vehicle controller sends a mode switching command to the drive motor controller, controlling the drive motor to switch from driving mode to generator mode;

[0126] The drive motor in power generation mode converts the vehicle's kinetic energy into three-phase alternating current, which is then rectified by the motor controller and output as DC regenerated electrical energy to the input of the power divider.

[0127] The vehicle controller determines the allocation ratio of regenerative energy based on the real-time state of charge of the first and second battery packs, and generates corresponding charging allocation instructions to send to the power divider.

[0128] In response to a charging distribution command, the power distributor delivers the received regenerated electrical energy to the first battery pack and / or the second battery pack for charging and storage according to the distribution ratio.

[0129] Furthermore, the vehicle controller sends a mode switching command to the drive motor controller. The process of controlling the drive motor to switch from drive mode to generator mode includes:

[0130] The vehicle controller generates a mode switching command message containing the target operating mode identifier and the target generated torque value;

[0131] The vehicle controller sends mode switching command messages to the drive motor controller via the vehicle control CAN bus;

[0132] The controller of the drive motor receives and parses the mode switching command message to obtain the target operating mode identifier and the target generating torque value;

[0133] The controller of the drive motor switches the control logic of its internal inverter from motor torque control to generator torque control according to the target operating mode identifier.

[0134] The controller of the drive motor adjusts the pulse width modulation signal of the power switching device in the inverter according to the target generating torque value, so that the drive motor generates braking torque corresponding to the target generating torque value and outputs three-phase AC power.

[0135] Specifically, the vehicle controller continuously monitors the analog voltage signal or digital switch signal from the brake pedal position sensor. When it detects that the brake pedal has been depressed and its travel exceeds a preset zero-position threshold, it determines that the brake pedal signal has been triggered. At the same time, the vehicle controller monitors and calculates the real-time power demand P of the vehicle. req When the calculated power demand is negative, it indicates that the vehicle needs to decelerate. If either the "brake pedal signal is triggered" or the "vehicle power demand is negative" condition is met, the vehicle controller determines that the vehicle is currently in a braking or coasting state suitable for energy recovery. After determining that the vehicle has entered the energy recovery state, the vehicle controller immediately generates a mode switching command. This command is encapsulated in the form of a CAN message, and its data field contains at least two key fields: the first is the target operating mode identifier, which is filled with a specific calibration value representing the "power generation mode", such as the hexadecimal number 0x02, to distinguish it from the "drive mode" of 0x01; the second is the target power generation torque value T. gen_target This value is negative, indicating the magnitude of the desired braking torque generated by the motor. Its absolute value can be obtained by looking up a table or by calculation. Based on the current vehicle speed v and the brake pedal opening α, it is obtained by consulting the preset three-dimensional pulse spectrum of "vehicle speed - braking intensity - target generated torque". The calculation formula can be expressed as:

[0136] T gen_target = -f(v,α);

[0137] Among them, the function f represents the mapping relationship defined by the calibration data, ensuring that the recovery intensity is smooth and meets the braking regulations;

[0138] The vehicle controller sends a mode switching command message containing the above information to the CAN receiver port of the drive motor controller via the vehicle's high-speed control CAN bus. After receiving the message, the drive motor controller's communication processing module parses the data field and extracts the target operating mode identifier and the target generated torque value T. gen_target Subsequently, its main control chip, based on the target operating mode identifier, calls and switches to the generator control subroutine. The core of this switching action lies in switching the internal inverter's control logic from motor torque control mode to generator torque control mode. Simultaneously, the control logic configures the energy flow direction of the inverter's power switching devices to flow from the motor side to the DC bus side. In generator mode, the drive motor operates as a generator, and the drive motor controller, based on the received target generator torque value T... gen_target Combined with the current motor speed n m Through its internal torque loop control algorithm, the corresponding q-axis current command I is calculated. q_cmd Using a space vector pulse width modulation algorithm, precise PWM drive signals are generated for the six IGBT power switches in the inverter. By applying these control signals, the motor is driven to generate signals consistent with T. gen_target The corresponding braking torque is generated, and simultaneously, three-phase alternating current is induced in the three-phase stator windings. This three-phase alternating current is rectified by the freewheeling diodes in the inverter or by actively controlled switching transistors, converting the alternating current into direct current. After being filtered by the DC-side bus capacitor of the inverter, this direct current outputs as regenerative electrical energy P in a voltage-stable DC form. regen And it is supplied to the DC power input terminal of the power divider;

[0139] Renewable energy P regen Simultaneously, the vehicle controller determines the energy distribution strategy based on the real-time state of charge (SOC1) of the first battery pack and the real-time state of charge (SOC2) of the second battery pack.

[0140] A preferred allocation strategy is the state-of-charge (SOC) equalization priority strategy, in which the vehicle controller calculates the allocation coefficient k. b1 and k b2 And satisfy k b1 +k b2 =1, the allocation coefficient can be determined by the following rules:

[0141] If both SOC1 and SOC2 are below their respective charging cutoff limits, the battery pack with the lower state of charge will be charged first. Specifically:

[0142] When SOC1 < SOC2, set k b1 =1.0, k b2 =0, meaning all recovered electrical energy is supplied to the first battery pack;

[0143] When SOC1 > SOC2, set k b1 =0,k b2 =1.0;

[0144] When the difference between SOC1 and SOC2 is less than 1%, k can be set. b1 =005,k b2 =0.5 to be evenly distributed. If the state of charge of one of the battery packs has reached the charging cutoff limit, then all the recovered energy will be distributed to the battery packs that are not fully charged.

[0145] The vehicle controller uses a predetermined allocation coefficient k. b1 and k b2 A charging distribution command message is generated and sent to the power distributor via the CAN bus. This command explicitly specifies the target charging power P of the first battery pack. ch1_target =k b1 ×P regen The target charging power P of the second battery pack ch2_target =k b2 ×P regen After receiving a charging distribution command, the power distributor's internal DC-DC conversion module or power routing switch will, according to the command, distribute the input regenerative electrical energy P... regen Press P ch1_target and P ch2_target The power is divided proportionally and sent to the charging management ports of the first and second battery packs respectively to complete the storage of electrical energy. When braking ends or the required power turns positive, the vehicle controller sends a command to exit the power generation mode and the system returns to normal driving state.

[0146] During vehicle operation, the system cyclically executes control command generation, energy recovery, and corresponding power supply management processes based on state of charge, enabling the first and second battery packs to alternately provide power for driving and charging.

[0147] Furthermore, the process of cyclically executing control command generation, energy recovery, and corresponding power supply management based on state of charge includes:

[0148] When the state of charge of both the first battery pack and the second battery pack is higher than the preset low charge threshold, the first battery pack and the second battery pack are controlled to jointly supply power to the drive motor.

[0149] During the period when the first battery pack and the second battery pack are supplying power together, when the state of charge of the first battery pack drops below a preset low charge threshold, the on-board generator is started to charge the first battery pack, and the second battery pack is controlled to supply power to the drive motor separately.

[0150] While the second battery pack is supplying power to the drive motor independently and the first battery pack is being charged by the on-board generator, when the state of charge of the second battery pack drops below a preset low charge threshold, the on-board generator is switched to charge the second battery pack, and the first battery pack is controlled to supply power to the drive motor independently.

[0151] During continuous vehicle operation, based on the changes in the state of charge of the first and second battery packs, the system cyclically executes a process from a shared power supply state, through a state of charging the first battery pack and supplying power independently to a state of charging the second battery pack and supplying power independently to a state of charging the second battery pack and supplying power independently to the first battery pack. The system also continuously performs an energy recovery process, thereby allowing the roles of the first and second battery packs to alternate between driving power supply and charging replenishment.

[0152] Specifically, after the vehicle starts, the vehicle controller first reads the initial state of charge (SOC) of the first battery pack. 1-init Initial State of Charge (SOC) of the Second Battery Pack 2-init The controller has a preset low power threshold (SOC). L If SOC is satisfied 1-init SOC L And SOC 2_init SOC L The system enters the first operating state, State_CO, where both battery packs provide power. In this state, the vehicle controller executes the aforementioned process, that is, dynamically allocating the target output power P of the first battery pack based on the real-time acquired SOC1 and SOC2. bat1_target With the target output power P of the second battery pack bat2_target It controls the power distributor to make both drive the motor together, while the on-board generator remains off;

[0153] In the State_CO state, the vehicle controller continuously monitors SOC1 and SOC2 in each control cycle. Once it detects that SOC1 < SOC2, it will take action. LThis triggers the first alternation event. After triggering, the vehicle controller performs a state switch, specifically, it jumps from State_CO to the second operating state, State_Ch1_Pow2, which is the first battery pack charging / second battery pack power supply state. It immediately executes the generation and sending of the first control command in the above process. Specifically, it sends a start and target speed command to the on-board generator controller, the generator starts and runs at the high-efficiency power generation point, and sends a first battery pack isolation and charging command to the power distributor. The power distributor controls the first power regulation module to stop working, disconnects the first battery pack from the drive circuit, and simultaneously imports the electrical energy output by the generator into the first battery pack through the charging circuit to charge it in a preset constant current or constant power mode. It sends a second battery pack independent power supply command to the power distributor, controlling the second power regulation module to adjust the output current of the second battery pack independently according to the real-time power demand of the vehicle. At this point, the system enters the first round of alternation, the role of the first battery pack changes to charging supplementation, and the role of the second battery pack changes to independent drive power supply.

[0154] In State_Ch1_Pow2, the vehicle controller continuously monitors the state of charge (SOC2) of the independently powered second battery pack. Once it detects that SOC2 < SOC... L This triggers the second alternation event. After triggering, the vehicle controller performs a state switch, specifically, it jumps from State_Ch1_Pow2 to the third operating state, State_Ch2_Pow1, which is the second battery pack charging / first battery pack power supply state. It immediately executes the second control command generation and sending in the above process. If the generator is already running, it skips the start command and executes the target switch, sending the second battery pack isolation and charging command to the power distributor. The power distributor controls the second power adjustment module to stop working, disconnects the second battery pack from the drive circuit, and switches the power output of the generator to the second battery pack to charge it. It sends the first battery pack independent power supply command to the power distributor. Since the first battery pack has recovered a certain amount of power during the charging process, the power distributor controls the first power adjustment module to reactivate and adjusts the output current of the first battery pack according to the power demand of the vehicle. At this point, the system completes the second round of alternation. The role of the second battery pack changes to "charging supplement" and the role of the first battery pack changes back to "independent drive power supply".

[0155] In State_Ch2_Pow1, the vehicle controller continuously monitors the State of Charge (SOC1) of the first battery pack that is independently powered. When it detects that SOC1 < SOC LThis indicates that after a complete cycle, the system state once again meets the conditions for triggering the first alternation event. At this time, the vehicle controller will execute a state transition, switching from State_Ch2_Pow1 back to State_Ch1_Pow2, and execute the first control command again. This process is exactly the same as described above. The system will cycle between the two states of State_Ch1_Pow2 and State_Ch2_Pow1. As long as the vehicle is continuously driving and the generator is working, it can be guaranteed that there is always one battery pack providing driving force to the vehicle, while the other battery pack is receiving efficient charging.

[0156] It is important to note that the aforementioned energy recovery process, as an independent, event-driven sub-process, runs through all the above operating states. Regardless of the system's main power supply state, as long as braking or coasting conditions are met, the vehicle controller immediately executes the energy recovery process in parallel, intelligently distributing regenerated electrical energy to the two battery packs according to the current strategy, continuously replenishing the system's energy. This cycle terminates when any of the following conditions are met: first, the vehicle stops moving, the power demand is zero and remains so for more than a set time; second, the driver actively shuts off the vehicle's power; third, the onboard generator stops working due to fuel depletion or other reasons, and both battery packs' state of charge (SOC) is below the threshold of compatibility (SOC). L The system cannot maintain alternating power supply. Through the above process, the present invention realizes that during vehicle operation, the first battery pack and the second battery pack automatically and cyclically alternate between the "drive unit" and the "energy storage unit" according to their state of charge. This working mode decouples the driving and charging processes, so that the vehicle does not need to stop to charge during long-distance driving, and can avoid the efficiency loss and battery stress caused by traditional range-extended vehicles, thus achieving efficient, continuous and reliable energy supply.

[0157] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for coordinating energy supply from an energy-saving vehicle-mounted generator and a battery, characterized in that, The method is applied to a collaborative power supply system, which includes a first battery pack, a second battery pack, an on-board generator, a drive motor, a vehicle controller, and a power divider. The method includes the following steps: The vehicle controller acquires vehicle status information and the state of charge of the first and second battery packs in real time. When the vehicle is in pure electric drive mode powered by the battery pack drive motor, the vehicle controller controls the power divider to make the first battery pack and the second battery pack jointly power the drive motor according to the state of charge of the first battery pack and the second battery pack. The vehicle controller makes a judgment based on the real-time acquired state of charge. If it is determined that the state of charge of the first battery pack is lower than a preset low charge threshold, a first control command is generated. If it is determined that the state of charge of the second battery pack is lower than the low charge threshold, a second control command is generated. When the vehicle is braking or coasting, the vehicle controller controls the drive motor to operate in energy recovery mode and delivers the generated regenerated electrical energy to the first battery pack and / or the second battery pack for storage through the power distributor; During vehicle operation, the system cyclically executes control command generation, energy recovery, and corresponding power supply management processes based on the state of charge, enabling the first battery pack and the second battery pack to alternately provide power for driving and charging.

2. The method for coordinated power supply of an energy-saving vehicle-mounted generator and battery according to claim 1, characterized in that, The process of acquiring vehicle status information and the state of charge of the first and second battery packs in real time through the vehicle controller includes: The vehicle controller periodically reads and parses vehicle speed signal messages (representing vehicle speed) and demand torque messages (representing driving requirements) through the vehicle CAN network. The vehicle controller calculates the real-time power demand of the vehicle based on the demand torque message and the current vehicle speed. The vehicle controller obtains the real-time voltage, real-time current and real-time temperature of the first battery pack and the second battery pack respectively; The vehicle controller calculates the real-time state of charge of the first battery pack based on the real-time voltage, real-time current and real-time temperature of the first battery pack. The vehicle controller calculates the real-time state of charge of the second battery pack based on the real-time voltage, real-time current and real-time temperature of the second battery pack.

3. The method for coordinated power supply of an energy-saving vehicle-mounted generator and battery according to claim 1, characterized in that, The process in which the first battery pack and the second battery pack jointly supply power to the drive motor according to a preset power distribution ratio includes: The vehicle controller compares the real-time state of charge of the first battery pack with the real-time state of charge of the second battery pack. The vehicle controller calculates the first target output power of the first battery pack and the second target output power of the second battery pack based on the comparison results and the preset state of charge balance strategy, wherein the sum of the first target output power and the second target output power is equal to the real-time power demand of the vehicle. The vehicle controller converts the first target output power and the second target output power into control signals for the first power adjustment module and the second power adjustment module in the power distributor, respectively. The power distributor responds to the control signal by controlling the output power from the first battery pack through the first power adjustment module and controlling the output power from the second battery pack through the second power adjustment module, so that the first battery pack and the second battery pack jointly supply power to the drive motor at the first target output power and the second target output power.

4. The method for coordinated power supply of an energy-saving vehicle-mounted generator and battery according to claim 3, characterized in that, The process by which the vehicle controller converts the first target output power and the second target output power into control signals for the first power adjustment module and the second power adjustment module in the power distributor includes: The vehicle controller calculates the first target current value or first duty cycle signal required by the first power adjustment module based on the first target output power and the real-time voltage of the first battery pack. The vehicle controller calculates the second target current value or second duty cycle signal required by the second power regulation module based on the second target output power and the real-time voltage of the second battery pack. The vehicle controller sends a first drive command containing the first target current value or the first duty cycle signal to the first power regulation module through the first control channel; The vehicle controller sends a second drive command, which includes the second target current value or the second duty cycle signal, to the second power regulation module through the second control channel.

5. The method for coordinated power supply of an energy-saving vehicle-mounted generator and battery according to claim 4, characterized in that, The workflow of the first power regulation module and the second power regulation module includes: In response to the received first drive command, the first power regulation module adjusts the conduction state or equivalent impedance of its switching device so that the current flowing through the first power regulation module matches the first target current value, or makes the pulse width of its output voltage correspond to the first duty cycle signal. In response to the received second drive command, the second power regulation module adjusts the conduction state or equivalent impedance of its switching device so that the current flowing through the second power regulation module matches the second target current value, or makes the pulse width of its output voltage correspond to the second duty cycle signal. The adjusted output current of the first battery pack and the output current of the second battery pack are combined at the power junction point of the power divider to jointly provide a total drive current to the input terminal of the drive motor.

6. The method for coordinated power supply of an energy-saving vehicle-mounted generator and battery according to claim 1, characterized in that, The generation process of the first control command and the second control command includes: The vehicle controller compares the real-time state of charge of the first battery pack with a preset first low charge threshold. If the real-time state of charge of the first battery pack is lower than the first low charge threshold, the vehicle controller generates a first control command that includes starting the on-board generator, charging the first battery pack, and isolating the first battery pack from the drive circuit. The vehicle controller compares the real-time state of charge of the second battery pack with a preset second low charge threshold. If the real-time state of charge of the second battery pack is lower than the second low charge threshold, the vehicle controller generates a second control command that includes starting the on-board generator, charging the second battery pack, and isolating the second battery pack from the drive circuit.

7. The method for coordinated power supply of an energy-saving vehicle-mounted generator and battery according to claim 1, characterized in that, When the vehicle is in a braking or coasting state, the process by which the vehicle controller controls the drive motor to operate in energy recovery mode includes: When the vehicle controller detects that the brake pedal signal is triggered or the vehicle power demand is negative, it determines that the vehicle is in a braking or coasting state. The vehicle controller sends a mode switching command to the controller of the drive motor to control the drive motor to switch from driving mode to power generation mode; In power generation mode, the drive motor converts the vehicle's kinetic energy into three-phase alternating current, which is then rectified by the motor controller and output as DC regenerated power to the input of the power distributor. The vehicle controller determines the allocation ratio of regenerative energy based on the real-time state of charge of the first battery pack and the second battery pack, and generates a corresponding charging allocation command to send to the power distributor. In response to the charging distribution command, the power distributor delivers the received regenerated electrical energy to the first battery pack and / or the second battery pack respectively for charging and storage according to the distribution ratio.

8. A method for coordinating energy supply from an energy-saving vehicle-mounted generator and a battery according to claim 7, characterized in that, The process by which the vehicle controller sends a mode switching command to the controller of the drive motor, controlling the drive motor to switch from drive mode to generator mode, includes: The vehicle controller generates a mode switching instruction message containing a target operating mode identifier and a target generated torque value; The vehicle controller sends the mode switching command message to the drive motor controller via the vehicle control CAN bus; The controller of the drive motor receives and parses the mode switching instruction message to obtain the target operating mode identifier and the target power generation torque value; The controller of the drive motor switches the control logic of its internal inverter from motor torque control to generator torque control according to the target operating mode identifier. The controller of the drive motor adjusts the pulse width modulation signal of the power switching device in the inverter according to the target generating torque value, so that the drive motor generates a braking torque corresponding to the target generating torque value and outputs three-phase AC power.

9. A method for coordinating energy supply from an energy-saving vehicle-mounted generator and a battery according to claim 1, characterized in that, The process of cyclically executing control command generation, energy recovery, and corresponding power supply management based on the stated state of charge includes: When the state of charge of both the first battery pack and the second battery pack is higher than a preset low charge threshold, the first battery pack and the second battery pack are controlled to jointly supply power to the drive motor. During the period when the first battery pack and the second battery pack are jointly powered, when the state of charge of the first battery pack drops below a preset low charge threshold, the on-board generator is started to charge the first battery pack, and the second battery pack is controlled to supply power to the drive motor alone. While the second battery pack is supplying power to the drive motor alone and the first battery pack is being charged by the vehicle generator, when the state of charge of the second battery pack drops below a preset low charge threshold, the vehicle generator is switched to charge the second battery pack, and the first battery pack is controlled to supply power to the drive motor alone. During continuous vehicle operation, based on the changes in the state of charge of the first battery pack and the second battery pack, the process of switching from the common power supply state, through the charging state of the first battery pack and the independent power supply state of the second battery pack, to the charging state of the second battery pack and the independent power supply state of the first battery pack is continuously executed, thereby alternating the roles of the first battery pack and the second battery pack between driving power supply and charging replenishment.

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