Energy recovery method for new energy vehicles

Abstract

The present invention relates to the field of energy recovery technology, specifically disclosing an energy recovery method for new energy vehicles, comprising the following steps: S1: calculating the maximum kinetic energy at time point t1 and the maximum converted electrical energy; determining whether the maximum converted electrical energy is fully stored in the capacitor based on the remaining capacity; S2: Step 1: obtaining driving information within a monitoring period, calculating the amount of electrical energy conversion based on the predicted vehicle speed obtained from a vehicle speed prediction model; if the average conversion power P ≤ Pys, executing Step 2; if the average conversion power P > Pys, executing Step 3; Step 2: the electrical energy converted from kinetic energy and the capacitor jointly charge the energy storage device; a new monitoring period is set, and Step 1 is repeated; Step 3: the electrical energy converted from kinetic energy simultaneously charges the energy storage device and the capacitor; a new monitoring period is set, and Step 1 is repeated. The present invention can delay the aging process of the energy storage device.

Description

Technical Field

[0001] The present invention relates to the technical field of energy recovery, and in particular to an energy recovery method for new energy vehicles. Background Art

[0002] As the global climate change problem becomes increasingly serious, reducing carbon emissions has become a global consensus. The promotion of new energy vehicles, as one of the important measures for carbon reduction, has one of its core competitive advantages in advanced energy recovery systems.

[0003] The Regenerative Braking System (RBS) converts kinetic energy that would otherwise be lost as heat during vehicle deceleration or braking into electrical energy and stores it in the battery for subsequent use, thereby optimizing overall energy efficiency.

[0004] During braking energy recovery, the energy storage device of a new energy vehicle frequently switches between charging and discharging states. Specifically, when the vehicle decelerates or brakes, the electric motor converts kinetic energy into electrical energy and stores it in the battery (charging). During driving, the battery releases electrical energy to drive the electric motor (discharging). With frequent energy recovery and release, the number of charge and discharge cycles of the energy storage device increases. Batteries have a finite lifespan and a certain number of cycles. Frequent charge and discharge cycles accelerate battery aging, causing a decrease in battery capacity and ultimately affecting its range. Summary of the Invention

[0005] The purpose of the present invention is to provide an energy recovery method for new energy vehicles to solve the following technical problems:

[0006] With frequent energy recovery and release, the number of charge and discharge cycles of the energy storage device will continue to increase. The battery has a certain service life and number of cycles. Frequent charge and discharge cycles will accelerate the aging process of the battery, causing the battery capacity to decrease, and ultimately affecting its endurance.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] An energy recovery method for a new energy vehicle, comprising a capacitor and an energy storage device, comprises the following steps:

[0009] S1: Determine the time point t1 when the vehicle starts braking, obtain the speed V0 of the vehicle at the time point t1, and calculate the maximum kinetic energy W max =(m×V0 2 ) / 2, m represents the total mass of the vehicle, calculate the maximum conversion energy Q max =η×W max , η represents the conversion efficiency of the vehicle’s kinetic energy into electrical energy;

[0010] Obtain the remaining capacity Qsy of the capacitor, if the maximum conversion energy Q max ≤0.8Qsy, the capacitor is adjusted to a charged state, and during the vehicle's braking process, all the electrical energy converted from kinetic energy is stored in the capacitor;

[0011] If the maximum conversion energy Q max >0.8Qsy, go to step S2;

[0012] S2: Step 1: Predict the vehicle speed at time point t1+t2, where t2 represents a preset prediction step size. Calculate the electric energy conversion amount Q1 based on the vehicle speed, and calculate the average conversion power P. If the average conversion power P ≤ Pys, proceed to step 2; if the average conversion power P > Pys, proceed to step 3.

[0013] Step 2: The electric energy converted from kinetic energy and the capacitor together charge the energy storage device; set a new monitoring period and repeat step 1;

[0014] Step 3: The electrical energy converted from kinetic energy charges the energy storage device and the capacitor at the same time; set a new monitoring period and repeat step 1.

[0015] As a further solution of the present invention: in step 1, the process of predicting the vehicle speed at time point t1+t2 includes:

[0016] Obtain driving information within a preset monitoring period [t1-T, t1], the driving information including vehicle speed information and road condition information, set a prediction duration t2, input the driving information into a pre-trained vehicle speed prediction model, and obtain a predicted vehicle speed V1 at time point t1+t2;

[0017] The process of pre-training the vehicle speed prediction model specifically includes:

[0018] Establishing a database, wherein the database stores driving information with the vehicle speed after the predicted time t2 marked;

[0019] A vehicle speed prediction model is established based on the deep learning model, and the vehicle speed prediction model is trained and verified based on the database to obtain a pre-trained vehicle speed prediction model.

[0020] As a further solution of the present invention: in the step 1, the average conversion rate P=Q1 / t2, the electric energy conversion amount .

[0021] As a further solution of the present invention: in the step S2, step 2 includes:

[0022] In the time period [t1, t2], the charging power is maintained at the average conversion power P to charge the energy storage device, and the capacitor is adjusted to a discharge state to charge the energy storage device, and the discharge power P1=Pys-P;

[0023] Set a new monitoring period [t1+t2-T, t1+t2] and repeat step 1 to obtain a new average conversion power;

[0024] Step three includes:

[0025] In the time period [t1, t2], the energy storage device is charged with the charging power maintained at the average conversion power threshold Pys, and the capacitor is adjusted to a charging state for charging, wherein the charging power P2 = P-Pys;

[0026] Set a new monitoring period [t1+t2-T, t1+t2] and repeat step 1 to obtain a new average conversion power.

[0027] As a further solution of the present invention: the step 1 further includes the following steps:

[0028] Obtain the difference between the predicted speed and the actual speed at the same time point. If the difference is greater than the preset difference threshold, mark the corresponding predicted speed as an abnormal speed measurement. Count the proportion of predicted speeds at abnormal speed measurement stations. If the proportion is greater than 0.3, send a message to report an error.

[0029] As a further solution of the present invention: in step S2, a maximum kinetic energy threshold is set. If the maximum kinetic energy W max ≤Wys, no energy recovery.

[0030] As a further solution of the present invention: the step S2 further includes a discharge step:

[0031] When the vehicle stops running and the energy storage device is charged, the capacitor is adjusted to a charging state to charge the energy storage device.

[0032] As a further solution of the present invention: when the remaining capacity Qsy of the capacitor is less than or equal to a preset value, the capacitor is no longer charged until the discharging step is performed.

[0033] As a further solution of the present invention: in the step 1, if the difference between the actual vehicle speed at the time point t1+t2 and the speed V0 is greater than the preset speed difference, the energy recovery system is not started and the braking system is used for deceleration.

[0034] Beneficial effects of the present invention: In this solution, first, by determining the time point t1 when the vehicle starts braking, obtaining the vehicle's speed V0 at that moment, and calculating the maximum kinetic energy, the potential for the vehicle's maximum kinetic energy to be converted into electrical energy during braking is accurately estimated to ensure the efficiency and accuracy of energy recovery; by calculating the maximum converted electrical energy and comparing it with the remaining capacity of the capacitor, it can be reasonably determined whether the capacitor needs to be adjusted to a charging state or to enter a subsequent step. If the maximum converted electrical energy is small (less than or equal to 0.8Qsy), the electrical energy can be directly stored in the capacitor to avoid the battery from being subjected to excessive charge and discharge loads, thereby reducing the number of battery cycles and helping to extend the battery life; if the maximum converted electrical energy is large (greater than 0.8Qsy), step S2 is entered. At this time, by obtaining driving information and inputting it into a pre-trained vehicle speed prediction model, the vehicle speed V1 at time point t1+t2 is predicted, and the amount of electrical energy conversion is calculated; by predicting the dynamic behavior of the vehicle, the energy recovery process can be more reasonably adjusted to ensure that the energy conversion between the battery and the capacitor is more balanced and accurate; it is worth noting that the vehicle speed information includes but is not limited to the vehicle speed , acceleration, steering angle and braking signal, etc., road condition information includes but is not limited to road inclination, vehicle distance and other information, which can be selected according to actual conditions; then, the capacitor is charged or discharged based on whether the average conversion power is greater than the charging power threshold Pys. If the average conversion power is greater than the charging power threshold, the energy storage device and the capacitor are charged at the same time by the electric energy converted from kinetic energy, avoiding charging the energy storage device with excessively high charging power, thereby reducing the aging rate of the battery, and storing excess electric energy in the capacitor, avoiding energy waste and improving energy recovery efficiency. The capacitor itself can adapt to higher charging and discharging speeds, so there is no risk of increasing capacitor aging; if the average conversion power is less than or equal to the charging power threshold, the electric energy converted from kinetic energy and the capacitor are used to charge the energy storage device together, because the energy storage device needs to be charged at this time, which can be counted as one charging cycle. Therefore, the electric energy in the capacitor is used to charge the energy storage device together, avoiding the increase in the number of charging cycles caused by using the capacitor alone to charge the energy storage device, thereby extending the life of the energy storage device and reducing the degree of aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention will be further described below with reference to the accompanying drawings.

[0036] Figure 1 It is a flow chart of an energy recovery method for new energy vehicles according to the present invention. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0038] See also Figure 1 As shown, the present invention is an energy recovery method for new energy vehicles, a capacitor and an energy storage device, comprising the following steps:

[0039] S1: Determine the time point t1 when the vehicle starts braking, obtain the speed V0 of the vehicle at the time point t1, and calculate the maximum kinetic energy W max =(m×V0 2 ) / 2, m represents the total mass of the vehicle, calculate the maximum conversion energy Q max =η×W max , η represents the conversion efficiency of the vehicle’s kinetic energy into electrical energy;

[0040] Obtain the remaining capacity Qsy of the capacitor, if the maximum conversion energy Q max ≤0.8Qsy, the capacitor is adjusted to a charged state, and during the vehicle's braking process, all the electrical energy converted from kinetic energy is stored in the capacitor;

[0041] If the maximum conversion energy Q max >0.8Qsy, go to step S2;

[0042] S2: Step 1: Obtain driving information within the preset monitoring period [t1-T, t1], the driving information includes vehicle speed information and road condition information, set the prediction time t2, input the driving information into the pre-trained vehicle speed prediction model, obtain the predicted vehicle speed V1 at the time point t1+t2, and calculate the electric energy conversion amount ;

[0043] If the average conversion power P = Q1 / t2 ≤ Pys, proceed to step 2, where Pys represents the preset charging function threshold;

[0044] If the average conversion power P>Pys, execute step 3;

[0045] Step 2: During the time period [t1, t2], the energy storage device is charged with the charging power maintained at the average conversion power P, and the capacitor is adjusted to a discharge state to charge the energy storage device, where the discharge power P1 = Pys-P;

[0046] Set a new monitoring period [t1+t2-T, t1+t2] and repeat step 1 to obtain a new average conversion power;

[0047] Step 3: During the time period [t1, t2], the energy storage device is charged with the charging power maintained at the average conversion power threshold Pys, and the capacitor is adjusted to a charging state for charging, wherein the charging power P2 = P-Pys;

[0048] Set a new monitoring period [t1+t2-T, t1+t2] and repeat step 1 to obtain a new average conversion power.

[0049] It should be noted that by determining the time point t1 when the vehicle starts braking, obtaining the vehicle's speed V0 at that moment, and calculating the maximum kinetic energy, the potential for the vehicle's maximum kinetic energy to be converted into electrical energy during braking can be accurately estimated to ensure the efficiency and accuracy of energy recovery. By calculating the maximum converted electrical energy and comparing it with the remaining capacity of the capacitor, it can be reasonably determined whether the capacitor needs to be adjusted to a charged state or to enter the subsequent steps. If the maximum converted electrical energy is small (less than or equal to 0.8Qsy), the electrical energy can be directly stored in the capacitor to avoid the battery from being subjected to excessive charge and discharge loads, thereby reducing the number of battery cycles and helping to extend the battery life. If the maximum converted electrical energy is large (greater than 0.8Qsy), step S2 is entered. At this time, by obtaining driving information and inputting it into the pre-trained vehicle speed prediction model, the vehicle speed V1 at time point t1+t2 is predicted, and the amount of electrical energy conversion is calculated. By predicting the dynamic behavior of the vehicle, the energy recovery process can be adjusted more reasonably to ensure that the energy conversion between the battery and the capacitor is more balanced and accurate. It is worth noting that the vehicle speed information includes but is not limited to vehicle speed, acceleration, Steering angle and braking signal, etc., road condition information includes but is not limited to road inclination, vehicle distance and other information, which can be selected according to actual conditions; then, the capacitor is charged or discharged based on whether the average conversion power is greater than the charging power threshold Pys. If the average conversion power is greater than the charging power threshold, the energy storage device and the capacitor are charged simultaneously by the electric energy converted from kinetic energy, avoiding charging the energy storage device with excessively high charging power, thereby reducing the aging rate of the battery, and storing excess electric energy in the capacitor, avoiding energy waste and improving energy recovery efficiency. The capacitor itself can adapt to higher charging and discharging speeds, so there is no risk of increasing capacitor aging; if the average conversion power is less than or equal to the charging power threshold, the electric energy converted from kinetic energy and the capacitor are used to charge the energy storage device together. Because the energy storage device needs to be charged at this time, it can be counted as one charging cycle. Therefore, the electric energy in the capacitor is used to charge the energy storage device together, avoiding the increase in the number of charging cycles caused by using the capacitor alone to charge the energy storage device, thereby extending the life of the energy storage device and reducing the degree of aging.

[0050] In another preferred embodiment of the present invention, in step S2, the process of pre-training the vehicle speed prediction model specifically includes:

[0051] Establishing a database, wherein the database stores driving information with the vehicle speed after the predicted time t2 marked;

[0052] A vehicle speed prediction model is established based on the deep learning model, and the vehicle speed prediction model is trained and verified based on the database to obtain a pre-trained vehicle speed prediction model.

[0053] Notably, the driving information contained in the database encompasses a variety of factors, including road conditions, driving behavior, and vehicle status. This ensures more comprehensive and accurate training for the speed prediction model, enhancing its generalization capabilities in practical applications. By building a speed prediction model based on a deep learning model, the complex nonlinear relationships in the data can be fully utilized to achieve highly accurate speed predictions. Training and validating the speed prediction model ensures its robustness and effectiveness, making its performance more stable across various driving scenarios. This provides a reliable predictive foundation for subsequent energy recovery strategies, enabling dynamic adjustment of charging and discharging strategies based on future vehicle speed changes in practical applications.

[0054] In another preferred embodiment of the present invention, the step 1 further includes the following steps:

[0055] Obtain the difference between the predicted speed and the actual speed at the same time point. If the difference is greater than the preset difference threshold, mark the corresponding predicted speed as an abnormal speed measurement. Count the proportion of predicted speeds at abnormal speed measurement stations. If the proportion is greater than 0.3, send a message to report an error.

[0056] It is understood that if the difference between the predicted and actual speeds exceeds a preset threshold, the predicted speed is marked as abnormal, promptly identifying and flagging deviations in the model's predictions, thereby preventing inaccurate predictions from impacting subsequent energy recovery strategies. The system also calculates the proportion of speeds predicted by abnormal speed stations. If the proportion is greater than 0.3, a message is sent to indicate an error. This provides the system with a self-correction mechanism, ensuring the stability and accuracy of the speed prediction model in practical applications. When the proportion of abnormal predictions is high, the system automatically issues a warning, indicating possible model issues or anomalies in the input data, facilitating timely adjustments and optimizations, thus avoiding energy waste or battery damage caused by abnormal predictions.

[0057] In another preferred embodiment of the present invention, in step S2, a maximum kinetic energy threshold is set. If the maximum kinetic energy W max ≤Wys, no energy recovery.

[0058] It's important to note that setting this maximum kinetic energy threshold effectively prevents energy recovery from occurring when the vehicle's kinetic energy is too low to be effectively converted into electricity. Continuing to recover energy when kinetic energy is insufficient is not only inefficient but can also lead to unnecessary damage to the battery and energy storage system. By setting a reasonable maximum kinetic energy threshold, the system automatically stops energy recovery when kinetic energy is low, avoiding unnecessary battery charge and discharge cycles, reducing the burden on the battery, and effectively extending its lifespan.

[0059] In another preferred embodiment of the present invention, the step S2 further includes a discharging step:

[0060] When the vehicle stops running and the energy storage device is charged, the capacitor is adjusted to a charging state to charge the energy storage device.

[0061] It should be noted that when the user is charging the energy storage device, after detecting this situation, the capacitor is adjusted to a discharged state to charge the energy storage device together. There is no need to use a separate capacitor to charge the energy storage device, thus avoiding additional charging cycles.

[0062] In another preferred embodiment of the present invention, when the remaining capacity Qsy of the capacitor is less than or equal to a preset value, the capacitor is no longer charged until the discharging step is performed.

[0063] In another preferred embodiment of the present invention, in step 1, if the difference between the actual vehicle speed at the time point t1+t2 and the speed V0 is greater than a preset speed difference, the energy recovery system is not activated and the braking system is used for deceleration.

[0064] It's worth noting that if the difference between the vehicle's actual speed at time t1+t2 and the predicted speed V0 is greater than the preset speed difference, this indicates that the vehicle is decelerating very rapidly and may require rapid braking to ensure safety. In this case, because the energy recovery system's braking is typically gentle and cannot meet the rapid deceleration requirements, the system decides not to activate the energy recovery system and instead uses the traditional braking system for deceleration.

[0065] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. An energy recovery method for new energy vehicles, comprising a capacitor and an energy storage device, characterized in that: The following steps are involved: S1: Determine the time point t1 when the vehicle starts braking, obtain the speed V0 of the vehicle at the time point t1, and calculate the maximum kinetic energy W max =(m×V0 2 ) / 2, m represents the total mass of the vehicle, calculate the maximum conversion energy Q max =η×W max , η represents the conversion efficiency of the vehicle’s kinetic energy into electrical energy; Obtain the remaining capacity Qsy of the capacitor, if the maximum conversion energy Q max ≤0.8Qsy, the capacitor is adjusted to a charged state, and during the vehicle's braking process, all the electrical energy converted from kinetic energy is stored in the capacitor; If the maximum conversion energy Q max >0.8Qsy, go to step S2; S2: Step 1: Predict the vehicle speed at time point t1+t2, where t2 represents a preset prediction step size. Calculate the electric energy conversion amount Q1 based on the vehicle speed and the average conversion power P. If the average conversion power P ≤ Pys, proceed to step 2, where Pys represents the charging power threshold. If the average conversion power P > Pys, proceed to step 3. Step 2: The electric energy converted from kinetic energy and the capacitor together charge the energy storage device; set a new monitoring period and repeat step 1; Step 3: The electrical energy converted from kinetic energy charges the energy storage device and the capacitor at the same time; set a new monitoring period and repeat step 1.

2. The energy recovery method for new energy vehicles according to claim 1, characterized in that: In step 1, the process of predicting the vehicle speed at time point t1+t2 includes: Obtain driving information within a preset monitoring period [t1-T, t1], the driving information including vehicle speed information and road condition information, set a prediction duration t2, input the driving information into a pre-trained vehicle speed prediction model, and obtain a predicted vehicle speed V1 at time point t1+t2; The process of pre-training the vehicle speed prediction model specifically includes: Establishing a database, wherein the database stores driving information with the vehicle speed after the predicted time t2 marked; A vehicle speed prediction model is established based on the deep learning model, and the vehicle speed prediction model is trained and verified based on the database to obtain a pre-trained vehicle speed prediction model.

3. The energy recovery method for new energy vehicles according to claim 2, characterized in that: In the step 1, the average conversion power P=Q1 / t2, the electric energy conversion amount .

4. The energy recovery method for new energy vehicles according to claim 3, characterized in that: In the step S2, step 2 includes: In the time period [t1, t2], the charging power is maintained at the average conversion power P to charge the energy storage device, and the capacitor is adjusted to a discharge state to charge the energy storage device, and the discharge power P1=Pys-P; Set a new monitoring period [t1+t2-T, t1+t2] and repeat step 1 to obtain a new average conversion power; Step three includes: In the time period [t1, t2], the energy storage device is charged with the charging power maintained at the average conversion power threshold Pys, and the capacitor is adjusted to a charging state for charging, wherein the charging power P2 = P-Pys; Set a new monitoring period [t1+t2-T, t1+t2] and repeat step 1 to obtain a new average conversion power.

5. The energy recovery method for new energy vehicles according to claim 4, characterized in that: The step 1 further includes the following steps: Obtain the difference between the predicted speed and the actual speed at the same time point. If the difference is greater than the preset difference threshold, mark the corresponding predicted speed as an abnormal speed measurement. Count the proportion of abnormal speed measurement to predicted speed. If the proportion is greater than 0.3, send a message to report an error.

6. The energy recovery method for new energy vehicles according to claim 1, characterized in that: In step S2, the maximum kinetic energy threshold is set. If the maximum kinetic energy W max ≤Wys, no energy recovery is performed, Wys represents the maximum kinetic energy threshold.

7. The energy recovery method for new energy vehicles according to claim 1, characterized in that: The step S2 further includes a discharge step: When the vehicle stops running and the energy storage device is charged, the capacitor is adjusted to a charging state to charge the energy storage device.

8. The energy recovery method for new energy vehicles according to claim 7, characterized in that: When the remaining capacity Qsy of the capacitor is less than or equal to the preset value, the capacitor is no longer charged until the discharging step is performed.

9. The energy recovery method for new energy vehicles according to claim 1, characterized in that: In the step 1, if the difference between the actual vehicle speed at the time point t1+t2 and the speed V0 is greater than the preset speed difference, the energy recovery system is not activated and the braking system is used for deceleration.

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