Adaptive energy recovery method for new energy vehicle

Abstract

The application discloses a new energy automobile adaptive energy recovery method, comprising: establishing an energy recovery benchmark MAP, a boundary MAP and an energy recovery calibration coefficient related to the whole vehicle operation scene; when the whole vehicle meets the energy recovery condition, the whole vehicle controller sends a torque request according to the benchmark MAP, and the motor controller feeds back the current torque after responding; the whole vehicle controller calculates the energy recovery calibration coefficient d, and determines the effective d value according to the relationship between the current torque and the benchmark value and the boundary value; the whole vehicle controller adjusts the torque request based on the effective d value and sends it, and the motor controller responds, and the cycle is repeated until the energy recovery state is exited. The new energy automobile adaptive energy recovery method can adaptively adjust the energy recovery strategy according to dynamic factors such as wind resistance, wheel resistance and slope by establishing the energy recovery MAP under different scenes, so that the vehicle can recover energy in an optimal way under various working conditions, the energy recovery efficiency is effectively improved, and the cruising range of the vehicle is increased.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, specifically, it relates to an adaptive energy recovery method for new energy vehicles. Background Technology

[0002] With the rapid development of the automotive industry, new energy vehicles have steadily increased their market share while ensuring drivability and power performance. Combined with the emergence of the energy crisis, the environmental pollution generated by new energy vehicles is far lower than that generated by fuel vehicles. However, the range problem of new energy vehicles has also been raised, and effective energy recovery can improve the overall range of the vehicle.

[0003] Currently, there are two main technical solutions for vehicle energy recovery design:

[0004] Firstly, a single energy recovery strategy is adopted, meaning that the same MAP (characteristic curve diagram) is used for energy recovery control during both coasting and braking recovery, regardless of the driving scenario.

[0005] Secondly, a three-level energy recovery strategy is adopted, which divides the energy recovery intensity into three levels: light, medium and heavy. Users can manually switch between these levels by triggering a switch according to their own driving habits or actual scenarios.

[0006] However, the aforementioned existing technologies have obvious limitations: for a single strategy, they cannot adapt to the complex and ever-changing scenarios during vehicle operation—such as different wind resistance, wheel configurations, vehicle weight, and uphill and downhill conditions, making it difficult to maximize energy recovery efficiency; for a three-level strategy, they can only provide a limited selection of fixed levels, which cannot fully cover all driving scenarios, nor can they automatically and accurately adjust according to real-time conditions, which not only affects energy recovery efficiency but may also adversely affect driving smoothness during coasting and braking. Summary of the Invention

[0007] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention provides an adaptive energy recovery method for new energy vehicles, with the goal of improving the overall vehicle energy recovery efficiency.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: an adaptive energy recovery method for new energy vehicles, comprising:

[0009] Establish energy recovery baseline MAP, boundary MAP, and energy recovery calibration coefficients relevant to vehicle application scenarios;

[0010] When the vehicle meets the energy recovery conditions, the vehicle controller sends a torque request based on the reference MAP, and the motor controller responds and feeds back the current torque.

[0011] The vehicle controller calculates the energy recovery calibration coefficient d and determines the effective d value based on the relationship between the current torque and the reference and boundary values;

[0012] The vehicle controller adjusts the torque request based on the effective d value and sends it, the motor controller responds, and this cycle continues until the energy recovery state is exited.

[0013] The steps for establishing the energy recovery baseline MAP, boundary MAP, and energy recovery calibration coefficients related to vehicle application scenarios include:

[0014] The vehicle application scenarios are established from three dimensions: wind resistance, wheel resistance, and slope. The influence of these three dimensions is comprehensively considered to obtain two boundary values ​​and a benchmark value for the external influence.

[0015] Energy recovery was calibrated based on simulated wind resistance, wheel resistance, and slope conditions of the whole vehicle, and energy recovery MAPs were established respectively.

[0016] The vehicle performs energy recovery under different conditions, collects relevant data to establish an energy recovery baseline MAP and two boundary MAPs, including a minimum boundary MAP and a maximum boundary MAP.

[0017] Calculate the ratios of all torques at the two boundary MAPs to the energy recovery baseline MAP, and obtain the dmax and dmin values ​​covering all points.

[0018] The factors affecting wind resistance include the vehicle speed and the wind speed under natural conditions; the factors affecting wheel resistance include road conditions, vehicle weight, and tire size; and the factors affecting slope are uphill and downhill road conditions.

[0019] The vehicle meets the energy recovery conditions as follows: the vehicle controller detects that the accelerator pedal travel value is 0 and the current motor speed is valid, covering coasting and braking energy recovery. During coasting energy recovery, the brake pedal travel value is invalid, while during braking energy recovery, the brake pedal travel value is valid.

[0020] The specific process of the vehicle controller sending a torque request based on the energy recovery reference MAP and the motor controller responding and feeding back the current torque is as follows: the vehicle controller sends an energy recovery request according to the energy recovery reference MAP parameters, based on the current motor speed and brake pedal travel value. The motor controller receives and responds to the torque request and sends the current torque after one cycle.

[0021] The specific method for calculating the energy recovery calibration coefficient d and determining the effective d value based on the relationship between the current torque and the reference value and boundary value is as follows:

[0022] The energy recovery calibration coefficient d = T / Tx3, where T is the current torque fed back by the motor controller, and Tx3 is the reference value in the energy recovery reference MAP;

[0023] When Tx1≥T>Tx3, d=T / Tx3 and d>1;

[0024] When T > Tx1, d is invalid, and d = dmax;

[0025] When T = Tx3, d = T / Tx3 and d = 1;

[0026] When Tx2≤T<Tx3, d=T / Tx3 and d<1;

[0027] When Tx2 > T, d is invalid, and d = dmin;

[0028] Where Tx1 is the minimum boundary value in the minimum boundary MAP, Tx2 is the maximum boundary value in the maximum boundary MAP, dmax is the upper limit of the torque ratio corresponding to the maximum boundary condition, and dmin is the lower limit of the torque ratio corresponding to the minimum boundary condition.

[0029] The vehicle controller adjusts the torque request based on the effective d value by sending a torque request that is the current torque request multiplied by 1 / d.

[0030] During the cycle, the vehicle controller sends torque requests every 50ms until the accelerator pedal value becomes valid, at which point energy recovery is discontinued.

[0031] Among the three simulated reference MAPs established, the baseline MAP and the two boundary MAPs are established by first performing energy recovery based on the baseline point under different conditions, and then performing energy recovery based on the three conditions of wind resistance, wheel resistance, and slope at different speeds combined with the throttle stroke value, and collecting all points.

[0032] The two boundary values ​​of the external influence are the comprehensive values ​​corresponding to F0max, F1max, and F2max and the comprehensive values ​​corresponding to F0min, F1min, and F2min. The benchmark value is the comprehensive value corresponding to F0, F1, and F2, where F0 is the dynamic wind resistance of the whole vehicle, F1 is the dynamic wheel resistance of the whole vehicle, and F2 is the dynamic slope force of the whole vehicle.

[0033] The adaptive energy recovery method for new energy vehicles of the present invention has the following beneficial effects:

[0034] 1. By establishing energy recovery MAPs for different scenarios, the energy recovery strategy can be adaptively adjusted according to dynamic factors such as wind resistance, wheel resistance, and slope, enabling vehicles to recover energy in a better way under various operating conditions, effectively improving energy recovery efficiency and increasing the vehicle's driving range.

[0035] 2. By monitoring torque in real time and dynamically adjusting the torque request, the problem of excessive or insufficient recovery intensity caused by a fixed energy recovery strategy in different scenarios is avoided. For example, in scenarios with high drag, the recovery intensity is appropriately adjusted to ensure the vehicle's coasting distance and driving smoothness; in scenarios with low drag, the recovery intensity is reasonably increased while ensuring braking safety, thus improving driving safety and comfort.

[0036] 3. This method can cover various situations such as coasting energy recovery and braking energy recovery, and takes into account different wind speeds, road conditions, vehicle loads, slopes and other factors, and has strong adaptability to various complex operating scenarios. Attached Figure Description

[0037] Figure 1 This is a flowchart for establishing the energy recovery coefficient of the whole vehicle;

[0038] Figure 2 This is a flowchart illustrating the application of the vehicle's energy recovery coefficient. Detailed Implementation

[0039] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. Rather, these embodiments are provided to make the disclosure of the present invention more thorough and complete.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0041] This invention provides an adaptive energy recovery method for new energy vehicles, comprising:

[0042] Establish energy recovery baseline MAP, boundary MAP, and energy recovery calibration coefficients relevant to vehicle application scenarios;

[0043] When the vehicle meets the energy recovery conditions, the vehicle controller sends a torque request based on the reference MAP, and the motor controller responds and feeds back the current torque.

[0044] The vehicle controller calculates the energy recovery calibration coefficient d and determines the effective d value based on the relationship between the current torque and the reference and boundary values;

[0045] The vehicle controller adjusts the torque request based on the effective d value and sends it, the motor controller responds, and this cycle continues until the energy recovery state is exited.

[0046] The steps for establishing the energy recovery baseline MAP, boundary MAP, and energy recovery calibration coefficients related to vehicle application scenarios include:

[0047] The vehicle application scenarios are established from three dimensions: wind resistance, wheel resistance, and slope. The influence of these three dimensions is comprehensively considered to obtain two boundary values ​​and a benchmark value for the external influence.

[0048] Energy recovery was calibrated based on simulated wind resistance, wheel resistance, and slope conditions of the whole vehicle, and energy recovery MAPs were established respectively.

[0049] The vehicle performs energy recovery under different conditions, collects relevant data to establish an energy recovery baseline MAP and two boundary MAPs, including a minimum boundary MAP and a maximum boundary MAP.

[0050] Calculate the ratios of all torques at the two boundary MAPs to the energy recovery baseline MAP, and obtain the dmax and dmin values ​​covering all points.

[0051] The factors affecting wind resistance include the vehicle speed and the wind speed under natural conditions; the factors affecting wheel resistance include road conditions, vehicle weight, and tire size; and the factors affecting slope are uphill and downhill road conditions.

[0052] The vehicle meets the energy recovery conditions as follows: the vehicle controller detects that the accelerator pedal travel value is 0 and the current motor speed is valid, covering coasting and braking energy recovery. During coasting energy recovery, the brake pedal travel value is invalid, while during braking energy recovery, the brake pedal travel value is valid.

[0053] The specific process of the vehicle controller sending a torque request based on the energy recovery reference MAP and the motor controller responding and feeding back the current torque is as follows: the vehicle controller sends an energy recovery request according to the energy recovery reference MAP parameters, based on the current motor speed and brake pedal travel value. The motor controller receives and responds to the torque request and sends the current torque after one cycle.

[0054] The specific method for calculating the energy recovery calibration coefficient d and determining the effective d value based on the relationship between the current torque and the reference value and boundary value is as follows:

[0055] The energy recovery calibration coefficient d = T / Tx3, where T is the current torque fed back by the motor controller, and Tx3 is the reference value in the energy recovery reference MAP;

[0056] When Tx1≥T>Tx3, d=T / Tx3 and d>1;

[0057] When T > Tx1, d is invalid, and d = dmax;

[0058] When T = Tx3, d = T / Tx3 and d = 1;

[0059] When Tx2≤T<Tx3, d=T / Tx3 and d<1;

[0060] When Tx2 > T, d is invalid, and d = dmin;

[0061] Where Tx1 is the minimum boundary value in the minimum boundary MAP, Tx2 is the maximum boundary value in the maximum boundary MAP, dmax is the upper limit of the torque ratio corresponding to the maximum boundary condition, and dmin is the lower limit of the torque ratio corresponding to the minimum boundary condition.

[0062] The vehicle controller adjusts the torque request based on the effective d value by sending a torque request that is the current torque request multiplied by 1 / d.

[0063] During the cycle, the vehicle controller sends torque requests every 50ms until the accelerator pedal value becomes valid, at which point energy recovery is discontinued.

[0064] Among the three simulated reference MAPs established, the baseline MAP and the two boundary MAPs are established by first performing energy recovery based on the baseline point under different conditions, and then performing energy recovery based on the three conditions of wind resistance, wheel resistance, and slope at different speeds combined with the throttle stroke value, and collecting all points.

[0065] The two boundary values ​​of the external influence are the comprehensive values ​​corresponding to F0max, F1max, and F2max and the comprehensive values ​​corresponding to F0min, F1min, and F2min. The benchmark value is the comprehensive value corresponding to F0, F1, and F2, where F0 is the dynamic wind resistance of the whole vehicle, F1 is the dynamic wheel resistance of the whole vehicle, and F2 is the dynamic slope force of the whole vehicle.

[0066] Specifically, in this embodiment of the invention, the adaptive energy recovery method for new energy vehicles requests the current torque demand of the vehicle controller (VCU) based on the current scenario, current speed, and accelerator pedal depth, according to different application scenarios of the vehicle.

[0067] In this embodiment of the invention, it is necessary to establish energy recovery-related parameters and a MAP, which specifically includes the following steps:

[0068] 1. Establish vehicle application scenarios: Consider the external impacts on the vehicle from three dimensions: wind resistance, wheel resistance, and gradient. Wind resistance is affected by vehicle speed and natural wind speed; wheel resistance is affected by road conditions, vehicle weight, and tire size; gradient is affected by uphill and downhill road conditions.

[0069] 2. Determine the parameter values ​​of external influences: Based on a comprehensive consideration of the influences of the above three dimensions, obtain two boundary values ​​(minimum boundary value and maximum boundary value) and a benchmark value for the external influences;

[0070] 3. Perform energy recovery calibration and establish MAP: Based on the three conditions of the whole vehicle simulation (minimum boundary condition, baseline condition, and maximum boundary condition), perform energy recovery calibration and establish energy recovery MAPs respectively;

[0071] 4. Establish reference MAP: The whole vehicle performs energy recovery under different conditions. First, energy recovery is performed based on the reference point. Then, according to different conditions and different speeds, energy recovery is performed in combination with the throttle (including the brake pedal travel value is equal to 0 and the vehicle is coasting) travel value. All points are collected to establish three simulated reference MAPs, including one energy recovery reference MAP and two boundary MAPs. The two boundary MAPs are the minimum boundary MAP and the maximum boundary MAP, respectively.

[0072] 5. Calculate the d value: The d value is the ratio of all torques between the two established boundary MAPs and the reference MAP, where dmax and dmin are the values ​​respectively, and the d value covers all points.

[0073] In this embodiment of the invention, the method for implementing energy recovery specifically includes the following steps:

[0074] 1. Detection of energy recovery trigger conditions: When the vehicle is in operation, the VCU detects that the accelerator pedal travel value is 0, covering coasting and braking energy recovery, and enters the energy recovery state;

[0075] 2. Initial torque request: The VCU responds to energy recovery based on the baseline MAP and sends a negative torque request, which is then responded to by the MCU.

[0076] 3. Calculate the d value: After one cycle, the VCU compares the current torque with the standard T value to obtain the d value;

[0077] 4. Adjust torque request: The VCU sends a torque request based on the current torque request multiplied by 1 / d.

[0078] 5. Responding to torque requests: The motor controller (MCU) responds to torque requests;

[0079] 6. Cycle and Exit: The above steps are repeated continuously within the recycling cycle until the accelerator pedal value is valid, then exit.

[0080] In this embodiment of the invention, based on the dynamic operating conditions of the vehicle under different conditions of wind resistance, wheel resistance, and slope, the MAP data of the torque analysis of the vehicle under different conditions are calibrated. The wind resistance affecting the dynamic operating conditions of the vehicle is due to the vehicle speed and the wind speed under natural conditions. The wheel resistance affecting the dynamic operating conditions of the vehicle is mainly affected by road conditions, vehicle mass, tire size, etc. The road conditions of going uphill and downhill also affect the intensity of the vehicle's recovery and braking distance.

[0081] The process for establishing the vehicle energy recovery coefficient is as follows: Figure 1 As shown, a vehicle performance analysis is required during energy recovery. This analysis needs to consider the following conditions: dynamic wind resistance = F0; dynamic wheel resistance = F1; dynamic slope force = F3. F0 considers the effects of vehicle speed and wind force. When the vehicle is static, the wind force values ​​in both directions are used as the design value for wind resistance f0, which is influenced by the vehicle body itself. F1 considers the effects of vehicle weight, road friction coefficient, and tire width during dynamic operation. F3 considers the force generated by the slope during dynamic operation, which affects the vehicle's dynamic performance.

[0082] In this embodiment of the invention, the boundary conditions and reference conditions are set as follows:

[0083] 1. Vehicle dynamic wind resistance = F0: The condition for setting the minimum wind force is the vehicle static wind force f0 combined with the minimum wind force condition under common vehicle conditions. The limit exceeding the less commonly used limit does not need to be considered, and this value is set as F0min; The condition for setting the vehicle static wind force f0 = 0 is set as F0; The condition for setting the vehicle static wind force f0 combined with the maximum wind force under common vehicle conditions is set as F0max. The limit exceeding the less commonly used limit does not need to be considered.

[0084] 2. Vehicle dynamic wheel resistance = F1; The establishment condition is that the vehicle mass is at standard load and the vehicle dynamic operation is on a design road with low resistance, so this value is set to F1min; The establishment condition is that the vehicle mass is at standard load and the vehicle dynamic operation is on a design road with normal resistance, so this value is set to F1; The establishment condition is that the vehicle mass is fully loaded + 1T (tons) and the vehicle dynamic operation is on a design road with high resistance, so this value is set to F1max.

[0085] 3. Vehicle dynamic gradient force = F3; the establishment condition is vehicle dynamic operation combined with commonly used uphill slopes, and the value is set to F2min; the establishment condition is vehicle dynamic operation combined with commonly used flat roads without slopes, and the value is set to F2; the establishment condition is vehicle dynamic operation combined with commonly used downhill slopes, and the value is set to F2max.

[0086] 4. Comprehensive conditions: The minimum boundary condition for dynamic energy recovery of the whole vehicle is established as: fmin=F1min+F2min+F3min, which serves as the minimum boundary condition for dynamic energy recovery of the whole vehicle.

[0087] Establish the energy recovery condition for the whole vehicle as a baseline condition: f = F1 + F2 + F3, which serves as the baseline boundary condition for the dynamic energy recovery of the whole vehicle.

[0088] The maximum boundary condition for dynamic energy recovery of the whole vehicle is established as: fmax=F1max+F2max+F3max;

[0089] Establish the conditions for the whole vehicle to be in the baseline energy recovery state. In combination with the above baseline conditions, f = F1 + F2 + F3 is used to calibrate the dynamic energy recovery of the whole vehicle. When calibrating the energy recovery of the whole vehicle under the road conditions that simulate the baseline conditions for dynamic energy recovery of the whole vehicle, it also satisfies the requirements of economy and drivability. The specific MAP of braking recovery is shown in Table 1 below.

[0090] Table 1. Vehicle Calibration MAP under Baseline Conditions

[0091]

[0092] In this embodiment of the invention, Table 1 above serves as the baseline MAP table for vehicle energy recovery. This baseline energy recovery MAP table needs to consider the vehicle's performance under different road conditions. 1. Based on the vehicle dynamic energy recovery baseline MAP, the minimum boundary for vehicle dynamic energy recovery is: fmin = F1min + F2min + F3min, which serves as the road condition for vehicle dynamic energy recovery. The vehicle controller (VCU) sequentially requests energy recovery from the MCU based on each point within the vehicle dynamic energy recovery baseline MAP. Simultaneously, the MCU sends the current torque after one cycle (20ms), and the VCU receives this message. This process continues, collecting all torque points from the messages received by the VCU to establish MAP1. The specific MAP1 is shown in Table 2 below.

[0093] Table 2 Minimum Boundaries for Vehicle Dynamic Recovery under Baseline Conditions & Vehicle Calibration MAP Table

[0094]

[0095] In this embodiment of the invention, Table 1 above serves as the baseline MAP table for vehicle energy recovery. This baseline MAP table needs to consider the vehicle's performance under different road conditions. 1. Based on the vehicle dynamic energy recovery baseline MAP, the vehicle dynamic baseline boundary condition is f = F1 + F2 + F3, which is used as the road condition for vehicle dynamic energy recovery. The vehicle controller (VCU) sequentially requests energy recovery from the MCU based on each point in the baseline MAP. Simultaneously, the MCU sends the current torque after one cycle (20ms), and the VCU receives this message. This process is repeated, collecting all torque points from the messages received by the VCU to establish MAP2. The specific MAP2 is shown in Table 3 below.

[0096] Table 3. Baseline Conditions & Vehicle Dynamic Recovery Baseline Conditions, Vehicle Calibration MAP Table

[0097]

[0098] In this embodiment of the invention, Table 1 above serves as the baseline MAP table for vehicle energy recovery. This baseline MAP table needs to consider the vehicle's performance under different road conditions. 1. Based on the baseline MAP for vehicle dynamic energy recovery, the maximum boundary for vehicle dynamic energy recovery is fmax = F1max + F2max + F3max, which is used as the road condition for vehicle dynamic energy recovery. The vehicle controller (VCU) sequentially requests energy recovery from the MCU based on each point within the baseline MAP. Simultaneously, the MCU sends the current torque after one cycle (20ms), and the VCU receives this message. This process is repeated, collecting all torque points from the messages received by the VCU to establish MAP3. The specific MAP3 is shown in Table 4 below.

[0099] Table 4. Baseline Conditions & Vehicle Dynamic Recovery Baseline Conditions, Vehicle Calibration MAP Table

[0100]

[0101]

[0102] In this embodiment of the invention, MAP1 is established as follows: according to the vehicle dynamic energy recovery benchmark MAP, the vehicle dynamic energy recovery minimum boundary fmin is used as the road condition for vehicle dynamic energy recovery. The VCU requests energy recovery from the MCU in sequence with each point in the benchmark MAP. After one cycle (20ms), the MCU sends the current torque. The VCU receives the message, collects all torque points, and establishes MAP1, where the torque value is TX1.

[0103] In this embodiment of the invention, MAP2 is established as follows: based on the vehicle dynamic energy recovery benchmark MAP, the vehicle dynamic benchmark boundary condition f is used as the road condition to perform vehicle dynamic energy recovery. Similarly, torque points are collected to establish MAP2, where the torque value is TX3.

[0104] In this embodiment of the invention, MAP3 is established as follows: based on the vehicle dynamic energy recovery benchmark MAP, the maximum boundary fmax of the vehicle dynamic energy recovery is used as the road condition for vehicle dynamic energy recovery. Similarly, torque points are collected to establish MAP3, where the torque value is TX2.

[0105] In this embodiment of the invention, the energy recovery calibration coefficient d is determined as follows:

[0106] 1. When d = TX1 / TX3, since TX1 is greater than TX3, d > 1.

[0107] 2. When d = TX3 / TX3, TX3 equals TX3, so d = 1.

[0108] 3. When d = TX2 / TX3, since TX2 is less than TX3, d is less than 1. The above calibration coefficients are the boundary coefficients for subsequent energy recovery calibration parameters.

[0109] In this embodiment of the invention, it is necessary to consider the recovery coefficient of the feedback torque after energy recovery under different conditions. Each point in the above MAP is assumed to have the following characteristics: minimum boundary condition TX1, reference boundary TX3, and maximum boundary condition TX2. An energy recovery calibration coefficient d is established: 1. where d = TX1 / TX3; TX1 and TX3 parameters need to correspond one-to-one in the parameter table, where TX1 is greater than TX3, then d > 1; 2. where d = TX3 / TX3; TX3 parameters need to correspond one-to-one in the parameter table, where TX3 is equal to TX3, then d = 1; 3. where d = TX2 / TX3; TX2 and TX3 parameters need to correspond one-to-one in the parameter table, where TX2 is less than TX3, then d is less than 1. These calibration coefficients are the boundary coefficients for subsequent energy recovery calibration parameters.

[0110] like Figure 2 The diagram shown is a flowchart of the application of the vehicle energy recovery coefficient. The following scheme is based on... Figure 2 The energy recovery status is determined by: judging the effectiveness of the current dynamic energy recovery based on the vehicle's dynamic accelerator pedal travel value and the current motor speed. When the accelerator pedal travel value = 0 and the current motor speed is valid, the vehicle enters the dynamic energy recovery state, which includes coasting energy recovery and braking energy recovery. Coasting energy recovery occurs when the vehicle's brake pedal travel value is invalid, while braking energy recovery occurs when the vehicle's brake pedal travel value is valid.

[0111] When the vehicle energy recovery status is met, the vehicle controller (VCU), combining the current motor speed and brake pedal travel value, sends a vehicle energy recovery request according to the reference MAP parameters (see Table 1 above). The motor controller (MCU) receives and responds to the torque request in the message signal. After one cycle (20ms), the motor controller (MCU) sends the current torque. The vehicle controller (VCU) receives this message and compares it with the reference value TX3, the minimum boundary value TX1, and the maximum boundary value TX2. It calculates the energy recovery calibration coefficient d = T / Tx3 and determines the value of d according to different torque relationships.

[0112] • When TX1≥T>TX3, d=T / TX3, and d>1;

[0113] • When T > TX1, it is invalid; use d = dmax.

[0114] When T = TX3, d = T / TX3, and d = 1;

[0115] • When TX2≤T<TX3, d=T / TX3, and d<1;

[0116] • When TX2 > T, it is invalid; press d = dmin.

[0117] All the above relationships need to correspond one-to-one with the TX1 value in Table 2, the TX2 value in Table 2, and the TX3 value in Table 4. Based on the above relationships, the calibration coefficient d value is determined. The torque T value requirement needs to be determined according to the current brake pedal travel value and the current motor speed based on the reference energy recovery MAP parameter table in Table 1. Then, the current torque requirement = T × d is calculated.

[0118] The vehicle controller (VCU) sends the calculated current torque request. In order to fully respond to the torque and cover the period from when the motor controller (MCU) receives the torque request to when it sends the current torque, the period for the VCU to send the torque request is 50ms. During this period, the MCU receives and responds to the torque request. At this time, the VCU needs to determine the current accelerator pedal travel value. If it is invalid, it will calculate the torque request repeatedly. If it is valid, it will exit energy recovery.

[0119] The adaptive energy recovery method for new energy vehicles of the present invention has the following advantages:

[0120] 1. Create boundary values ​​for all influencing conditions during vehicle energy recovery, covering all conditions during vehicle energy recovery;

[0121] 2. Based on the MAP parameters of the baseline energy recovery, simulate the baseline conditions, minimum boundary values, and maximum boundary values ​​to establish the torque MAP diagram for the next cycle;

[0122] 3. Establish the current energy recovery calibration coefficient;

[0123] 4. Establish the current calibration coefficient based on the current motor speed and brake pedal travel value; combine the calibration coefficient with the current status and the reference MAP value to determine the current energy recovery value;

[0124] 5. Improve the vehicle's energy recovery efficiency and drivability.

[0125] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other situations without modification, are all within the protection scope of the present invention.

Claims

1. An adaptive energy recovery method for new energy vehicles, characterized in that, include: Establish energy recovery baseline MAP, boundary MAP, and energy recovery calibration coefficients relevant to vehicle application scenarios; When the vehicle meets the energy recovery conditions, the vehicle controller sends a torque request based on the reference MAP, and the motor controller responds and feeds back the current torque. The vehicle controller calculates the energy recovery calibration coefficient d and determines the effective d value based on the relationship between the current torque and the reference and boundary values; The vehicle controller adjusts the torque request based on the effective d value and sends it, the motor controller responds, and this cycle continues until the energy recovery state is exited.

2. The adaptive energy recovery method for new energy vehicles according to claim 1, characterized in that, The steps for establishing the energy recovery baseline MAP, boundary MAP, and energy recovery calibration coefficients related to vehicle application scenarios include: The vehicle application scenarios are established from three dimensions: wind resistance, wheel resistance, and slope. The influence of these three dimensions is comprehensively considered to obtain two boundary values ​​and a benchmark value for the external influence. Energy recovery was calibrated based on simulated wind resistance, wheel resistance, and slope conditions of the whole vehicle, and energy recovery MAPs were established respectively. The vehicle performs energy recovery under different conditions, collects relevant data to establish an energy recovery baseline MAP and two boundary MAPs, including a minimum boundary MAP and a maximum boundary MAP. Calculate the ratios of all torques at the two boundary MAPs to the energy recovery baseline MAP, and obtain the dmax and dmin values ​​covering all points.

3. The adaptive energy recovery method for new energy vehicles according to claim 2, characterized in that, The factors affecting wind resistance include the vehicle speed and the wind speed under natural conditions; the factors affecting wheel resistance include road conditions, vehicle weight, and tire size; and the factors affecting slope are uphill and downhill road conditions.

4. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, The vehicle meets the energy recovery conditions as follows: the vehicle controller detects that the accelerator pedal travel value is 0 and the current motor speed is valid, covering coasting and braking energy recovery. During coasting energy recovery, the brake pedal travel value is invalid, while during braking energy recovery, the brake pedal travel value is valid.

5. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, The specific process of the vehicle controller sending a torque request based on the energy recovery reference MAP and the motor controller responding and feeding back the current torque is as follows: the vehicle controller sends an energy recovery request according to the energy recovery reference MAP parameters, based on the current motor speed and brake pedal travel value. The motor controller receives and responds to the torque request and sends the current torque after one cycle.

6. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, The specific method for calculating the energy recovery calibration coefficient d and determining the effective d value based on the relationship between the current torque and the reference value and boundary value is as follows: The energy recovery calibration coefficient d = T / Tx3, where T is the current torque fed back by the motor controller, and Tx3 is the reference value in the energy recovery reference MAP; When Tx1≥T>Tx3, d=T / Tx3 and d>1; When T > Tx1, d is invalid, and d = dmax; When T = Tx3, d = T / Tx3 and d = 1; When Tx2≤T<Tx3, d=T / Tx3 and d<1; When Tx2 > T, d is invalid, and d = dmin; Where Tx1 is the minimum boundary value in the minimum boundary MAP, Tx2 is the maximum boundary value in the maximum boundary MAP, dmax is the upper limit of the torque ratio corresponding to the maximum boundary condition, and dmin is the lower limit of the torque ratio corresponding to the minimum boundary condition.

7. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, The vehicle controller adjusts the torque request based on the effective d value by sending a torque request that is the current torque request multiplied by 1 / d.

8. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, During the cycle, the vehicle controller sends torque requests every 50ms until the accelerator pedal value becomes valid, at which point energy recovery is discontinued.

9. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, Among the three simulated reference MAPs established, the baseline MAP and the two boundary MAPs are established by first performing energy recovery based on the baseline point under different conditions, and then performing energy recovery based on the three conditions of wind resistance, wheel resistance, and slope at different speeds combined with the throttle stroke value, and collecting all points.

10. The adaptive energy recovery method for new energy vehicles according to any one of claims 1 to 3, characterized in that, The two boundary values ​​of the external influence are the comprehensive values ​​corresponding to F0max, F1max, and F2max and the comprehensive values ​​corresponding to F0min, F1min, and F2min. The benchmark value is the comprehensive value corresponding to F0, F1, and F2, where F0 is the dynamic wind resistance of the whole vehicle, F1 is the dynamic wheel resistance of the whole vehicle, and F2 is the dynamic slope force of the whole vehicle.

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