A traditional fuel commercial vehicle electric management optimization method and system based on joint simulation

Abstract

The application provides a traditional fuel commercial vehicle electric management optimization method and system based on joint simulation, and relates to the technical field of vehicle energy management and simulation calibration. The steps of the method include: S1, collecting real vehicle basic data under each scene and performing pretreatment operation; S2, building a high-precision vehicle longitudinal dynamics and electrical system physical model; S3, controlling the generator by using an intermittent power generation control strategy; S4, dynamically adjusting the engine throttle opening at the moment when the generator is connected and disconnected. The beneficial effects are as follows: the SOC value is dynamically corrected, which can eliminate the SOC cumulative error in simulation; a generator control strategy is set, which can effectively reduce fuel consumption; the operation interval adjustment rule is tightened, which can prevent the operation interval of the generator from frequently changing due to the fluctuation of the load rate near the upper and lower limits of the economic load; according to the generator transient torque change amount, the torque fluctuation caused by the load mutation can be offset.

Description

Technical Field

[0001] This invention relates to the field of vehicle energy management and simulation calibration technology, specifically to a method and system for optimizing the energy management of traditional fuel commercial vehicles based on co-simulation. Background Technology

[0002] Traditional vehicle electrical management strategy development relies heavily on real-vehicle calibration, which is time-consuming and costly. Furthermore, existing simulation methods cannot accurately reproduce the transient torque interference to the engine during generator switching, leading to distorted fuel consumption optimization assessments. Simultaneously, current traditional vehicle generators often employ continuous power generation or simple threshold start-stop control strategies. Regardless of whether the engine is operating in high-efficiency or low-efficiency conditions, the generator is constantly under load or frequently and erratically switched on and off, making it difficult to match the engine's optimal fuel economy range. This results in low overall vehicle fuel efficiency and poor adaptability to different operating conditions. Summary of the Invention

[0003] The main objective of this invention is to provide a method and system for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation, thereby solving the problems mentioned in the background art.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for optimizing the electrical management of traditional fuel commercial vehicles based on co-simulation, comprising the following steps: S1. Collect basic vehicle data in various scenarios and perform preprocessing operations; S2. Build a high-precision physical model of the vehicle's longitudinal dynamics and electrical system; S3. Use the generator intermittent power generation control strategy to control the generator; S4. Dynamically adjust the engine throttle opening at the moment the generator is switched on and off.

[0005] Furthermore, the basic data of the actual vehicle includes: engine characteristic parameters, transmission system and vehicle chassis parameters, generator characteristic parameters, and battery characteristic parameters; The scenarios include: long-distance highway cruising, short-distance urban delivery, idling, continuous uphill and continuous downhill.

[0006] Furthermore, the preprocessing operations include: outlier handling, noise filtering, time axis synchronization, and normalization.

[0007] Furthermore, the physical model includes: engine model, transmission system model, electrical circuit model, and vehicle and driver model; The electrical circuit model includes: generator model, battery model, and electrical load model.

[0008] Furthermore, the battery model is built based on the ampere-hour integration method, and the open-circuit voltage (OCV) is introduced to correct the state of charge (SOC) in the battery model; the SOC correction process is as follows: When the correction trigger condition is met, the current value of the open circuit voltage is deduced from the battery terminal voltage and the battery DC internal resistance, and then the theoretical value of SOC is determined according to the OCV-SOC curve; the correction step number is set, and within the correction step number, the SOC is corrected in combination with the theoretical value of SOC to obtain the corrected value of SOC. The correction trigger condition is: the electrical load is less than the preset correction load threshold and the corresponding duration is greater than the preset correction time threshold.

[0009] Furthermore, the detailed process of step S3 is as follows: S301. Extract reference parameter data from the high-precision vehicle longitudinal dynamics and electrical system physical model; S302. Based on the engine's universal characteristic curve, pre-calibrate the upper and lower limits of the economic load to determine the engine's current operating range; the operating range is divided into high-efficiency operating range and low-efficiency operating range; S303. The battery is partitioned according to its SOC (State of Charge), and the partitioning rules are as follows: The upper and lower thresholds of the partition are preset. When the SOC is greater than the upper threshold, the battery is in the high charge zone. When the SOC is less than the lower threshold, the battery is in the low charge zone. Otherwise, the battery is in the medium charge zone. S304. Determine the generator control strategy based on the battery zone and the real-time operating range of the generator, specifically: When the battery is in the high charge zone, the generator control strategy is: the generator is disconnected, and the entire vehicle's electrical load is powered entirely by the battery; When the battery is in the medium charge range, the generator control strategy is as follows: if the engine is in the high-efficiency operating range, the generator is turned on, and the generator simultaneously supplies power to the load and charges the battery; if the engine is in the low-efficiency operating range, the generator is turned off, and the battery supplies power alone. When the battery is in a low charge range, the generator control strategy is as follows: the generator is turned on, and at this time, the generator continues to generate electricity regardless of whether the engine is in the high-efficiency range.

[0010] Furthermore, the calibration process for the upper and lower limits of economic load is as follows: Based on the engine's minimum effective fuel consumption rate, a fuel consumption threshold is defined. The area between the minimum effective fuel consumption rate and the fuel consumption threshold is the high-efficiency operating range. For each speed point, the upper and lower limits of the load rate corresponding to its high-efficiency operating range are found. The upper limit of the load rate is recorded as the upper limit of the economic load, and the lower limit of the load rate is recorded as the lower limit of the economic load. The process for determining the current operating range of the engine is as follows: The initial operating range of the engine is determined based on the initial operating range determination conditions. In subsequent moments, the real-time operating range of the generator is determined based on the engine's operating range adjustment rules.

[0011] Furthermore, the initial operating range determination condition is as follows: when the engine's initial load rate is greater than the lower limit of economic load and less than the upper limit of economic load, and at the same time the engine's initial effective fuel consumption rate is less than the fuel consumption threshold, the engine's initial operating range is determined to be an efficient operating range; otherwise, the engine's initial operating range is determined to be an inefficient operating range. The adjustment rules are as follows: When the engine was in an inefficient operating range at the previous moment, if the engine's current load rate is greater than the sum of the lower limit of economic load and the hysteresis width and less than the difference between the upper limit of economic load and the hysteresis width, and at the same time the engine's current effective fuel consumption rate is less than the difference between the fuel consumption threshold and the fuel consumption adjustment value, the engine is determined to have entered the efficient operating range from the inefficient operating range. When the engine was in the high-efficiency operating range at the previous moment, if the engine's current load rate is less than the difference between the lower limit of economic load and the hysteresis width, and the engine's current effective fuel consumption rate is greater than the sum of the fuel consumption threshold and the fuel consumption adjustment value, or if the engine's current load rate is greater than the sum of the upper limit of economic load and the hysteresis width, and the engine's current effective fuel consumption rate is greater than the sum of the fuel consumption threshold and the fuel consumption adjustment value, then the engine is determined to have entered the low-efficiency operating range from the high-efficiency operating range.

[0012] Furthermore, the detailed process of step S4 is as follows: S401. First, calculate the instantaneous estimated value of the generator drag torque at the moment the generator is turned on or off. S402. The instantaneous change estimate of the generator drag torque is used as the engine's compensation torque increment. The engine's compensation torque increment is converted into the throttle opening feedforward compensation amount. The engine throttle opening is dynamically adjusted according to the throttle opening feedforward compensation amount.

[0013] This invention also provides a traditional fuel-powered commercial vehicle electrical management optimization system based on co-simulation, used to implement the steps in the above method, including: The multi-source data acquisition and preprocessing module is used to collect basic vehicle data in various scenarios and perform preprocessing operations. The physical simulation module, built upon the simulation model, communicates with the multi-source data acquisition and preprocessing module to build a high-precision physical model of the vehicle's longitudinal dynamics and electrical system. The control strategy module, built on a simulation model, communicates with the multi-source data acquisition, preprocessing, and physical simulation modules. It is used to control the generator using the generator intermittent power generation control strategy and to compensate for torque fluctuations caused by sudden changes in generator load at the moment the generator is turned on or off. The data interaction module serves as a data transmission channel between the physical simulation module and the control strategy module, enabling bidirectional communication between them.

[0014] The beneficial effects are as follows: (1) By combining the open-circuit voltage characteristic curve to dynamically correct the estimated value, the accumulated error of SOC in the simulation can be eliminated; (2) Through the real-time closed-loop joint simulation architecture, a two-way causal coupling mechanism between the physical model and the control strategy was established, enabling the strategy model to perceive the change in transient fuel consumption rate of the engine in real time and immediately feed back the generator control command, thus realizing the strong correlation between electrical balance and fuel consumption response. (3) Set up an intermittent power generation control strategy based on dual decision-making of engine load range and battery SOC, control the generator to stop generating power in the low load range of the engine and intelligently replenish power in the high efficiency range, and achieve systematic optimization of the overall fuel consumption of the vehicle under the dual constraints of maintaining the target vehicle speed and battery power balance. (4) The transient torque prediction calculation method based on the exponential function is adopted. The throttle opening is dynamically adjusted according to the prediction value at the moment of generator connection / disconnection to perform feedforward compensation, effectively offsetting the torque fluctuation caused by sudden load change and ensuring stable engine operation. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the steps in the method of the present invention; Figure 2 This is a flowchart of the generator intermittent power generation control logic in the method of the present invention; Figure 3 This is a framework diagram of the co-simulation model of the present invention. Detailed Implementation

[0016] Example 1 like Figures 1-2 As shown, a traditional fuel-powered commercial vehicle electrical management optimization method based on co-simulation includes the following steps: S1. Collect basic vehicle data in various scenarios and perform preprocessing operations; The basic data of the actual vehicle includes: engine characteristic parameters, transmission system and vehicle chassis parameters, generator characteristic parameters, and battery characteristic parameters; Engine characteristic parameters cover the full speed range and full load range; the full speed range is from idle speed to rated speed, with a step size of 40 rpm; the full load range is from 0 to 100% load, with a step size of 5%. Engine characteristic parameters include: maximum external characteristic torque at different speeds, effective fuel consumption rate at different speeds and loads, equivalent moment of inertia of the engine crankshaft system, transmission ratio of the generator pulley in the front-end gear train, and the engine universal characteristic curve. Effective fuel consumption rate is defined as the ratio of hourly fuel consumption to effective output power. The equivalent moment of inertia of the engine crankshaft system can be obtained through torsional vibration testing or calculation using a three-dimensional model of the components. The transmission ratio of the generator pulley in the front-end gear train is the ratio of the engine crankshaft pulley diameter to the generator pulley diameter. The engine universal characteristic curve is essentially a set of speeds and loads corresponding to a set of effective fuel consumption rates, maximum external characteristic torque, and minimum operating speeds. The maximum external characteristic torque is the maximum torque that the engine can output at that speed. By using interpolation to make the discrete correspondence between effective fuel consumption rate and speed and load continuous, and using the load corresponding to the maximum external characteristic torque and the minimum operating speed as the upper limit of the load constraint and the lower limit of the speed constraint, respectively, the universal characteristic curve can be obtained. The parameters of the transmission system and the vehicle chassis include: the clutch friction coefficient, the transmission ratio of each gear, the transmission ratio of the final drive, the transmission efficiency of the drive shaft, the equivalent moment of inertia of the transmission system in each gear, the vehicle curb weight, the air resistance coefficient, the frontal area, the tire rolling radius, the rolling resistance coefficient, and the driving resistance characteristics under different slopes. The transmission ratio and transmission efficiency are obtained through bench transmission efficiency tests, and the resistance coefficient is calculated by back-calculation through coasting tests. The coasting tests must be conducted on a level paved road surface in a windless environment. The vehicle speed-time curve from initial speed to stop is recorded, and the rolling resistance and air resistance parameters are calculated by back-calculation through the longitudinal dynamic equation. The generator characteristic parameters cover the full speed range and the full excitation current range; the full excitation current range is from zero current to rated current, with a step size of 4A. The generator characteristic parameters include: generator rotor speed, generator rotor angular velocity, generator output electrical power, generator input mechanical power, output terminal voltage at different speeds and excitation currents, no-load output voltage at different speeds under rated excitation, maximum output current at different speeds under rated excitation current, input shaft drag torque at different speeds and excitation currents, input shaft drag torque at different speeds and output currents, and steady-state power generation efficiency at the same speed but different output power. The expression for steady-state power generation efficiency is as follows: (1); in, Generator rotor speed, For the generator to output electrical power, To input mechanical power into the generator, This is the output voltage. For output current, For input shaft drag torque, The generator rotor angular velocity is denoted as ω. It should be noted that the excitation current is a control input variable actively applied during the test, and the output current is the output result under the corresponding scenario. These two are not generator characteristic parameters. However, the maximum output current corresponding to different speeds under rated excitation is the maximum value of the output current under each scenario, which is the maximum output current that the generator can produce. This is a generator characteristic parameter. Battery characteristic parameters are obtained through charge and discharge tests, including: OCV-SOC curve, battery DC internal resistance at different temperatures and SOCs, charge and discharge efficiency at different current rates, and battery rated capacity. In the OCV-SOC curve, OCV is the open-circuit voltage, and SOC is the battery state of charge in percentage form. After the battery is fully charged, it is discharged with a small constant current. After discharging 5% of the capacity, it is left to stand for 2 hours, and the open-circuit voltage is measured to obtain the corresponding relationship between SOC and COV for the entire SOC range, which is the OCV-SOC curve. The entire SOC range refers to the SOC range of 0 to 100%. The scenarios include: long-distance highway cruising, short-distance urban delivery, idling, continuous uphill and continuous downhill driving; Preprocessing operations include: outlier handling, noise filtering, time axis synchronization, and normalization. Outlier handling can use the commonly used 3 The criteria remove outliers and use interpolation algorithms to fill in the missing values ​​that result after removal; Commonly used noise filtering methods include Kalman filtering and low-pass filtering to remove high-frequency interference. Timeline synchronization involves aligning various types of data according to a unified timestamp. Normalization unifies the range of data values ​​to 0~1, avoiding the impact of inconsistent parameter ranges on calculations.

[0017] S2. Build a high-precision physical model of the vehicle's longitudinal dynamics and electrical system. Since the focus of the physical model here is on the construction of physical components, the simulation model selected here should have built-in physical component models, such as GT-Suite software. The physical model includes: engine model, powertrain model, electrical circuit model, and vehicle and driver model; The engine model is built based on the effective fuel consumption rate under different speeds and loads, the equivalent rotational inertia of the engine crankshaft system, and the transmission ratio of the generator pulley in the front-end gear train. Since the effective fuel consumption rate under different speeds and loads is inherently discrete, while the engine model requires a continuous relationship, the discrete relationship needs to be converted into a continuous relationship. Since a set of effective fuel consumption rates corresponds to a set of speeds and loads, the bilinear interpolation method can be used to perform linear interpolation from the speed and load dimensions respectively to obtain the continuous relationship between the effective fuel consumption rate and the speed and load. The transmission system model includes: the transmission chain model and the mechanical transmission efficiency parameters of the components in the transmission chain; the components in the transmission chain model include: clutch, gearbox and final drive. The electrical circuit model includes: generator model, battery model, and electrical load model; The generator model is built based on the steady-state power generation efficiency, moment of inertia and input shaft drag torque under different speeds and excitation currents of the target generator at different speeds and output powers. The steady-state power generation efficiency and input shaft drag torque under different speeds and excitation currents are also discrete data and need to be processed into continuous data. Linear interpolation can be used to achieve this. The excitation current changes as follows: when the generator control signal is switched from off to on, the excitation current rises according to the first-order inertial link, and the corresponding generating torque also gradually increases; when the generator control signal is switched from on to off, the excitation current decays through the freewheeling circuit, and the generating torque gradually decreases; based on the correspondence between different excitation currents at different speeds and the input shaft drag torque, the value of the input shaft drag torque can be obtained. The battery model is built based on the ampere-hour integration method and is corrected by introducing open-circuit voltage; the parameters in the battery model include: battery state of charge and battery terminal voltage; The ampere-hour integration method calculates the change in battery charge by integrating the charging and discharging current over time. The discrete expression for the battery's state of charge is as follows: (2); in, For the first The state of charge of the step, For the first The battery current is negative during charging and positive during discharging. For charge / discharge efficiency, the charging efficiency value is used during charging, and the discharging efficiency value is used during discharging. For the simulation step size, this embodiment uses 0.001s. This refers to the rated capacity of the battery. The battery terminal voltage is determined by the open-circuit voltage, internal resistance voltage drop, and state of charge (SOC), as shown in the following expression: (3); in, This refers to the battery terminal voltage. The open-circuit voltage can be obtained from the OCV-SOC curve. This is the battery's DC internal resistance. This value can be determined by continuously converting the battery's DC internal resistance at different temperatures and SOCs, and then determining it based on the SOC and temperature values. Because the ampere-hour integration method has accumulated errors, the SOC deviation will gradually increase. Therefore, the OCV is periodically corrected. The correction process is as follows: When the correction trigger condition is met, the current value of the open circuit voltage can be deduced by combining the battery terminal voltage and the battery DC internal resistance value with formula (3), and the theoretical value of SOC can be determined by the OCV-SOC curve; set the correction step number, and within the correction step number, combine the theoretical value of SOC to correct SOC and obtain the corrected value of SOC. The correction trigger condition is: the electrical load is less than the preset correction load threshold and the corresponding duration is greater than the preset correction time threshold; the correction load threshold can be set to 5%, and the correction time threshold can be set to 10s; The expression for the correction value of SOC is as follows: (4); in, This is the correction value for SOC. This is the theoretical value of SOC. To correct for the gain, this value is preset based on the calibration results of the actual vehicle; The electrical load model is built based on time-domain data of electrical loads collected under different scenarios. The vehicle and driver models include: the vehicle longitudinal dynamics model and the PID driver speed tracking controller model; The expression for the longitudinal dynamics model of the whole vehicle is as follows: (5); in, The total mass of the vehicle. For time, For vehicle speed, For the driving force of the wheels, For rolling resistance, For air resistance, For slope resistance; In the PID driver speed tracking controller model, the controller output is positive when it is the accelerator pedal opening and negative when it is the brake pedal opening. The controller input is the difference between the target vehicle speed and the real-time vehicle speed.

[0018] S3. Use a generator intermittent power generation control strategy to control the generator; the control strategy focuses on logical operations and needs to be able to work in conjunction with GT-Suite software, therefore MATLAB software is selected for simulation; the detailed process of this step is as follows: S301. Extract reference parameter data from the high-precision vehicle longitudinal dynamics and electrical system physical model; the reference parameters include: engine speed, engine output torque, engine load rate, engine effective fuel consumption rate, engine throttle opening, generator power output, battery SOC, vehicle electrical load power, vehicle speed, gear, and driving resistance; the load rate is defined as the ratio of the current output torque to the maximum external characteristic torque at the same speed; the engine throttle opening is related to the engine speed and engine output torque, and a set of engine throttle openings corresponding to engine speed and engine output torque can be calibrated through simulation, and the continuous correspondence between engine throttle opening and engine speed and engine output torque can be obtained by interpolation; Some of the reference parameters are given by the physical model and the actual vehicle data, while others are obtained by high-precision simulation tests of the vehicle's longitudinal dynamics and electrical system physical model. S302. Based on the engine's universal characteristic curve, pre-calibrate the upper and lower limits of the economic load to determine the engine's current operating range; the operating range is divided into high-efficiency operating range and low-efficiency operating range; The calibration process for the upper and lower limits of economic load is as follows: Based on the engine's minimum effective fuel consumption rate, a fuel consumption threshold is defined. In this embodiment, the fuel consumption threshold is defined as the product of the minimum effective fuel consumption rate and the high-efficiency zone tolerance coefficient. The high-efficiency zone tolerance coefficient is preset based on the actual vehicle calibration results. The area between the minimum effective fuel consumption rate and the fuel consumption threshold is the high-efficiency operating range. For each speed point, the upper and lower limits of the load rate corresponding to its high-efficiency operating range can be found according to the universal characteristic curve. The upper limit of the load rate is recorded as the upper limit of the economic load, and the lower limit of the load rate is recorded as the lower limit of the economic load. For different engines, at a given speed, the lower the effective fuel consumption rate, the better its economy. Therefore, the load rate corresponding to its lowest effective fuel consumption rate must be the optimal economic load rate. To the left of the optimal economic load rate, the fuel consumption threshold must correspond to a load rate whose value is less than the optimal economic load rate. This load rate is the lower limit of the economic load. To the right of the optimal economic load rate, there are two situations: 1. The effective fuel consumption rate corresponding to all load rates to the right of the optimal economic load rate is less than the fuel consumption threshold. In this case, all load rates to the right of the optimal economic load rate are more economical than the load rate corresponding to the fuel consumption threshold. In this case, the upper limit of the economic load is directly set to the maximum load rate, i.e., 100%. 2. The effective fuel consumption rate to the right of the optimal economic load rate shows an upward trend. There are some load rates whose effective fuel consumption rate is greater than the fuel consumption threshold. Therefore, there must be a load rate whose effective fuel consumption rate is equal to the fuel consumption threshold. In this case, this load rate is taken as the upper limit of the economic load. The process for determining the current operating range of the engine is as follows: The initial operating range of the engine is determined based on the initial operating range determination conditions of the engine. In subsequent moments, the real-time operating range of the generator is determined based on the engine's operating range adjustment rules. The initial operating range determination criteria are as follows: when the engine's initial load rate is greater than the lower limit of economic load and less than the upper limit of economic load, and at the same time the engine's initial effective fuel consumption rate is less than the fuel consumption threshold, the engine's initial operating range is determined to be an efficient operating range; otherwise, the engine's initial operating range is determined to be an inefficient operating range. To prevent frequent changes in the generator's operating range due to load factor fluctuations near the upper and lower limits of economic load, the standard for changes in the operating range is tightened, and the adjustment rules are set as follows: When the engine was in an inefficient operating range at the previous moment, if the engine's current load rate is greater than the sum of the lower limit of economic load and the hysteresis width and less than the difference between the upper limit of economic load and the hysteresis width, and simultaneously satisfies the condition that the engine's current effective fuel consumption rate is less than the difference between the fuel consumption threshold and the fuel consumption adjustment value, then the engine is determined to have entered the efficient operating range from the inefficient operating range. The expression is as follows: (6); in, This represents the engine's current load rate. , These are the lower limit and the upper limit of economic load, respectively. The hysteresis width, The effective fuel consumption rate at the current moment. This is the fuel consumption threshold. This is the fuel consumption adjustment value; When the engine was in its high-efficiency operating range at the previous moment, if the engine's current load rate is less than the difference between the lower limit of economic load and the hysteresis width, and the engine's current effective fuel consumption rate is greater than the sum of the fuel consumption threshold and the fuel consumption adjustment value, or if the engine's current load rate is greater than the sum of the upper limit of economic load and the hysteresis width, and the engine's current effective fuel consumption rate is greater than the sum of the fuel consumption threshold and the fuel consumption adjustment value, then the engine is determined to have entered a low-efficiency operating range. The expression is as follows: (7); The hysteresis width ranges from 2% to 5%, and the fuel consumption adjustment value is generally taken as 2 to 5 g / (kW). h), whose unit is consistent with the effective fuel consumption rate and is determined by the definition of effective fuel consumption rate; S303. The battery is partitioned according to its SOC (State of Charge), and the partitioning rules are as follows: The upper and lower thresholds of the partition are preset. When the SOC is greater than the upper threshold, the battery is in the high charge zone. When the SOC is less than the lower threshold, the battery is in the low charge zone. Otherwise, the battery is in the medium charge zone. The upper threshold of the partition is greater than the lower threshold. The upper and lower thresholds of the partition are preset based on the actual vehicle calibration results. S304. Determine the generator control strategy based on the battery zone and the real-time operating range of the generator, specifically: In this application, the engine outputs rotational mechanical energy, which drives the generator to rotate. The generator converts the mechanical energy into electrical energy, and the two are coupled to form a vehicle power generation unit. When the battery is in the high charge zone, the generator control strategy is: the generator is disconnected, and the entire vehicle's electrical load is powered entirely by the battery; When the battery is in the medium charge range, the generator control strategy is as follows: if the engine is in the high-efficiency operating range, the generator is turned on, and the generator simultaneously supplies power to the load and charges the battery; if the engine is in the low-efficiency operating range, the generator is turned off, and the battery supplies power alone. When the battery is in a low charge range, the generator control strategy is as follows: the generator is turned on, and at this time, the generator continues to generate electricity regardless of whether the engine is in the high-efficiency range.

[0019] S4. At the instant the generator is switched on and off, the engine throttle opening is dynamically adjusted based on the instantaneous estimated value of the generator's drag torque to compensate for torque fluctuations caused by sudden changes in generator load. The detailed process is as follows: S401. First, calculate the instantaneous estimated value of the generator drag torque at the moment the generator is switched on or off; the expression for the instantaneous estimated value of the generator drag torque at the moment of switching on is as follows: (8); in, This is an estimated instantaneous change in generator drag torque; specifically, it is the estimated instantaneous change in generator drag torque at the moment of connection. To control the timing of command issuance, This represents the increment of the generator's drag torque in steady state. This value is the difference between the input shaft drag torque value in steady state after switching on and the input shaft drag torque value in steady state before switching on. To ensure the estimated start-up time constant, this value is matched with the actual excitation time constant of the motor; The instantaneous estimated value of the generator drag torque at the moment of disconnection is expressed as follows: (9); in, To disconnect the estimated time constant, this value is matched with the generator excitation freewheeling decay time constant; here... The instantaneous change estimate of the generator drag torque at the moment of disconnection; S402. The instantaneous change estimate of the generator drag torque represents the load disturbance change value. The engine needs to output a corresponding compensation torque increment to offset the disturbance. Therefore, the instantaneous change estimate of the generator drag torque is used as the compensation torque increment of the engine. Based on the continuous correspondence between throttle opening, engine speed and engine output torque, the compensation torque increment of the engine is converted into the throttle opening feedforward compensation amount. The engine throttle opening is dynamically adjusted according to the throttle opening feedforward compensation amount within the estimated time constant of on or off.

[0020] Example 2 like Figure 3 As shown in the illustration, and further illustrated in Example 1, a conventional fuel-powered commercial vehicle electrical management optimization system based on co-simulation includes: The multi-source data acquisition and preprocessing module is used to collect basic vehicle data in various scenarios and perform preprocessing operations. It should be noted that, unlike the acquisition modules in other common systems that use data acquisition devices such as various sensors, the multi-source data acquisition and preprocessing module in this embodiment also includes a real vehicle platform and a bench test platform. That is, the multi-source data acquisition and preprocessing module in this embodiment will also collect data obtained after the real vehicle and bench test platform tests.

[0021] The physical simulation module, built upon the simulation model, communicates with the multi-source data acquisition and preprocessing module to build a high-precision physical model of the vehicle's longitudinal dynamics and electrical system; the simulation model of this module is generally built based on GT-Suite software.

[0022] The control strategy module, built on a simulation model, communicates with the multi-source data acquisition and preprocessing module and the physical simulation module. It is used to control the generator using the generator intermittent power generation control strategy and to compensate for torque fluctuations caused by sudden changes in generator load at the moment the generator is turned on or off. The simulation model of this module is generally built on MATLAB software.

[0023] The data interaction module serves as a data transmission channel between the physical simulation module and the control strategy module, enabling bidirectional communication between them.

[0024] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation, characterized in that, Includes the following steps: S1. Collect basic vehicle data in various scenarios and perform preprocessing operations; S2. Build a high-precision physical model of the vehicle's longitudinal dynamics and electrical system; S3. Use the generator intermittent power generation control strategy to control the generator; S4. Dynamically adjust the engine throttle opening at the moment the generator is switched on and off.

2. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation as described in claim 1, characterized in that, The basic data of the actual vehicle includes: engine characteristic parameters, transmission system and vehicle chassis parameters, generator characteristic parameters, and battery characteristic parameters; The scenarios include: long-distance highway cruising, short-distance urban delivery, idling, continuous uphill and continuous downhill.

3. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation as described in claim 1, characterized in that, Preprocessing operations include: outlier handling, noise filtering, time axis synchronization, and normalization.

4. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation as described in claim 1, characterized in that, The physical model includes: engine model, powertrain model, electrical circuit model, and vehicle and driver model; The electrical circuit model includes: generator model, battery model, and electrical load model.

5. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation according to claim 4, characterized in that, The battery model is built based on the ampere-hour integral method, and the open-circuit voltage (OCV) is introduced to correct the state of charge (SOC) in the battery model; the SOC correction process is as follows: When the correction trigger condition is met, the current value of the open circuit voltage is deduced from the battery terminal voltage and the battery DC internal resistance, and then the theoretical value of SOC is determined from the OCV-SOC curve. Set the correction step number, and within the correction step number, correct the SOC by combining the theoretical SOC value to obtain the corrected SOC value; The correction trigger condition is: the electrical load is less than the preset correction load threshold and the corresponding duration is greater than the preset correction time threshold.

6. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation according to claim 5, characterized in that, The detailed process of step S3 is as follows: S301. Extract reference parameter data from the high-precision vehicle longitudinal dynamics and electrical system physical model; S302. Based on the engine's universal characteristic curve, pre-calibrate the upper and lower limits of the economic load to determine the engine's current operating range; the operating range is divided into high-efficiency operating range and low-efficiency operating range; S303. The battery is partitioned according to its SOC (State of Charge), and the partitioning rules are as follows: The upper and lower thresholds of the partition are preset. When the SOC is greater than the upper threshold, the battery is in the high charge zone. When the SOC is less than the lower threshold, the battery is in the low charge zone. Otherwise, the battery is in the medium charge zone. S304. Determine the generator control strategy based on the battery zone and the real-time operating range of the generator, specifically: When the battery is in the high charge zone, the generator control strategy is: the generator is disconnected, and the entire vehicle's electrical load is powered entirely by the battery; When the battery is in the medium charge range, the generator control strategy is as follows: if the engine is in the high-efficiency operating range, the generator is turned on, and the generator simultaneously supplies power to the load and charges the battery; if the engine is in the low-efficiency operating range, the generator is turned off, and the battery supplies power alone. When the battery is in a low charge range, the generator control strategy is as follows: the generator is turned on, and at this time, the generator continues to generate electricity regardless of whether the engine is in the high-efficiency range.

7. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation according to claim 6, characterized in that, The calibration process for the upper and lower limits of economic load is as follows: Based on the engine's minimum effective fuel consumption rate, a fuel consumption threshold is defined. The area between the minimum effective fuel consumption rate and the fuel consumption threshold is the high-efficiency operating range. For each speed point, the upper and lower limits of the load rate corresponding to its high-efficiency operating range are found. The upper limit of the load rate is recorded as the upper limit of the economic load, and the lower limit of the load rate is recorded as the lower limit of the economic load. The process for determining the current operating range of the engine is as follows: The initial operating range of the engine is determined based on the initial operating range determination conditions. In subsequent moments, the real-time operating range of the generator is determined based on the engine's operating range adjustment rules.

8. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation according to claim 7, characterized in that, The initial operating range determination condition is: when the engine's initial load rate is greater than the lower limit of economic load and less than the upper limit of economic load, and at the same time the engine's initial effective fuel consumption rate is less than the fuel consumption threshold, the engine's initial operating range is determined to be the high-efficiency operating range. Otherwise, the engine's initial operating range is determined to be an inefficient operating range; The adjustment rules are as follows: When the engine was in an inefficient operating range at the previous moment, if the engine's current load rate is greater than the sum of the lower limit of economic load and the hysteresis width and less than the difference between the upper limit of economic load and the hysteresis width, and at the same time the engine's current effective fuel consumption rate is less than the difference between the fuel consumption threshold and the fuel consumption adjustment value, the engine is determined to have entered the efficient operating range from the inefficient operating range. When the engine was in the high-efficiency operating range at the previous moment, if the engine's current load rate is less than the difference between the lower limit of economic load and the hysteresis width, and the engine's current effective fuel consumption rate is greater than the sum of the fuel consumption threshold and the fuel consumption adjustment value, or if the engine's current load rate is greater than the sum of the upper limit of economic load and the hysteresis width, and the engine's current effective fuel consumption rate is greater than the sum of the fuel consumption threshold and the fuel consumption adjustment value, then the engine is determined to have entered the low-efficiency operating range from the high-efficiency operating range.

9. The method for optimizing the electrical management of traditional fuel-powered commercial vehicles based on co-simulation according to claim 6, characterized in that, The detailed process of step S4 is as follows: S401. First, calculate the instantaneous estimated value of the generator drag torque at the moment the generator is turned on or off. S402. The instantaneous change estimate of the generator drag torque is used as the engine's compensation torque increment. The engine's compensation torque increment is converted into the throttle opening feedforward compensation amount. The engine throttle opening is dynamically adjusted according to the throttle opening feedforward compensation amount.

10. A traditional fuel-powered commercial vehicle electrical management optimization system based on co-simulation, used to implement the steps in the method of any one of claims 1 to 9, characterized in that, include: The multi-source data acquisition and preprocessing module is used to collect basic vehicle data in various scenarios and perform preprocessing operations. The physical simulation module, built upon the simulation model, communicates with the multi-source data acquisition and preprocessing module to build a high-precision physical model of the vehicle's longitudinal dynamics and electrical system. The control strategy module, built on a simulation model, communicates with the multi-source data acquisition, preprocessing, and physical simulation modules. It is used to control the generator using the generator intermittent power generation control strategy and to compensate for torque fluctuations caused by sudden changes in generator load at the moment the generator is turned on or off. The data interaction module serves as a data transmission channel between the physical simulation module and the control strategy module, enabling bidirectional communication between them.

Images