A power dynamic management method for a new energy vehicle

Abstract

The application discloses a power dynamic management method of a new energy automobile, belongs to the technical field of new energy automobiles, and is applied to a power dynamic management system of a new energy automobile. The power dynamic management system comprises a power supply subsystem, an electric drive subsystem and an accessory subsystem. The power supply subsystem comprises a power battery pack and a power generation module. The electric drive subsystem and the accessory subsystem are connected with the power supply subsystem, and the electric drive subsystem is connected with the power battery pack. The power dynamic management method of the new energy automobile comprises the following steps: collecting power supply information of the power supply subsystem; calculating allowable power and actual output power of the power battery pack; performing one-level iteration calculation on the allowable power of the power battery pack and the actual output power of the power battery pack, and then performing two-level iteration calculation to obtain a target two-level iteration result; judging a driving state of the new energy automobile, and calculating final allowable output power of the electric drive subsystem according to the driving state and the target two-level iteration result.

Description

Technical Field

[0001] This invention belongs to the field of new energy vehicle technology, specifically relating to a method for dynamic power management of new energy vehicles. Background Technology

[0002] Vehicle power distribution strategy is one of the core technologies for the overall control of new energy vehicles such as pure electric vehicles, fuel cell vehicles, and hybrid electric vehicles. In addition to the electric drive system, new energy vehicles also have accessory subsystems, including DC-DC converters, oil pumps, and air conditioning. The power of these components is mainly provided by the power battery pack and generator module. An unreasonable power distribution strategy can lead to insufficient sub-drive power of the electric drive system, limited performance, and even over-discharge of the power battery. Traditional power distribution strategies use parameter calibration to allocate power, accurately calibrating the power of all accessories in the accessory subsystem when all are operating. Then, the allowable power of the electric drive subsystem is obtained by subtracting the calibrated accessory power from the power subsystem power composed of the power battery pack and generator module. However, this power distribution strategy inevitably leads to power waste in the power subsystem, preventing the electric drive subsystem's dynamic performance and electro-regenerative braking performance from being fully utilized. Accurately obtaining the real-time power consumption of the accessory subsystem is crucial for calculating the allowable electric / generator power of the electric drive subsystem. This is generally achieved by installing numerous sensors to obtain voltage and current information to calculate the power consumption, but this increases manufacturing costs.

[0003] In summary, the current power distribution strategy of new energy vehicles leads to power waste in the power subsystem, which prevents the electric drive subsystem from fully utilizing its power and electro-regenerative braking performance, and may even cause over-discharge of the power battery. In order to accurately obtain the real-time power consumption of the accessory subsystem, some systems use the method of adding many sensors to obtain the power consumption of each part of the accessory subsystem, but this increases manufacturing costs. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamic power management method for new energy vehicles, which can solve the problem that the current power allocation strategy of new energy vehicles causes power waste in the power subsystem, which prevents the power and electric feedback performance of the electric drive subsystem from being fully utilized, and may even lead to over-discharge of the power battery. In order to accurately obtain the real-time power consumption of the accessory subsystem, some methods use the method of adding many sensors to obtain the power consumed by each part of the accessory subsystem, but this increases the technical problem of manufacturing costs.

[0005] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0006] This invention provides a power dynamic management method for new energy vehicles, applied to a power dynamic management system for new energy vehicles. The power dynamic management system includes a power supply subsystem, an electric drive subsystem, and an accessory subsystem. The power supply subsystem includes a power battery pack and a power generation module. The electric drive subsystem and the accessory subsystem are both connected to the power supply subsystem. The electric drive subsystem is connected to the power battery pack. The power dynamic management method for new energy vehicles includes:

[0007] S101: Collect power information of the power subsystem, wherein the power information includes the actual current of the power battery pack. I Actual voltage U Maximum permissible charge and discharge current I p The output power of the power generation module E p ;

[0008] S102: Calculate the allowable power and actual output power of the power battery pack using the power information;

[0009] S103: Perform a first-level iterative calculation on the allowable power and the actual output power of the power battery pack to obtain the target first-level iterative result;

[0010] S104: Perform second-level iteration calculations based on the first-level iteration results of the target to obtain the second-level iteration results of the target;

[0011] S105: Determine the driving state of the new energy vehicle, and calculate the final allowable output power of the electric drive subsystem based on the driving state and the target second-level iteration result, wherein the driving state includes electric state and regenerative braking state.

[0012] In this embodiment of the invention, by acquiring the power information of the power supply subsystem and employing a two-stage power iteration calculation method, different driving states of the new energy vehicle are distinguished, and the final allowable output power of the electric drive subsystem is calculated. Without needing to obtain the working status and power of each accessory, the allowable power of the electric drive subsystem is dynamically adjusted, fully utilizing the power of the power supply subsystem. This avoids the power waste caused by directly calibrating the power of the accessory subsystems and fully leverages the dynamic rationality and electro-regenerative performance of the electric drive subsystem, preventing over-discharge of the power battery pack. While improving the overall vehicle performance, this avoids the increased costs associated with adding numerous sensors to acquire power information from various parts of the accessory subsystems, thus enhancing the product's competitiveness. Attached Figure Description

[0013] Figure 1This is a flowchart illustrating a power dynamic management method for new energy vehicles provided in an embodiment of the present invention.

[0014] Figure 2 This is a schematic diagram of the power dynamic management system for a new energy vehicle provided in an embodiment of the present invention.

[0015] The realization of the objective, functional characteristics and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0017] The following detailed description, in conjunction with the accompanying drawings, of the power dynamic management method for new energy vehicles provided by the present invention through specific embodiments and application scenarios, will be provided in detail.

[0018] Reference Figure 1 The diagram shows a flowchart of a power dynamic management method for new energy vehicles provided by an embodiment of the present invention.

[0019] Reference Figure 2 The diagram shows a schematic diagram of the power dynamic management system for a new energy vehicle provided in an embodiment of the present invention.

[0020] This invention provides a power dynamic management method for new energy vehicles, applied to a power dynamic management system for new energy vehicles. The power dynamic management system includes a power supply subsystem, an electric drive subsystem, and an accessory subsystem. The power supply subsystem includes a power battery pack and a power generation module. The electric drive subsystem and the accessory subsystem are both connected to the power supply subsystem. The electric drive subsystem is connected to the power battery pack. The power dynamic management method for new energy vehicles includes:

[0021] S101: Collect power information of the power subsystem, wherein the power information includes the actual current of the power battery pack. I Actual voltage U Maximum permissible charge and discharge current I p The output power of the power generation module E p .

[0022] It should be noted that, as the vehicle's power supply system, the rationality of the power distribution within the power subsystem directly affects the vehicle's operational stability, comfort, and operability. In practical applications, accurately obtaining the actual current of the power subsystem is crucial. I Actual voltage U Maximum permissible charge and discharge current I p The output power of the power generation module E p Based on the power information of each power source in the power subsystem, the calculated power information conforms to the actual power supply capacity of the entire power subsystem. This avoids directly calibrating the power consumption of each accessory, maximizes the power supply capacity of the power subsystem to the electric drive subsystem, and uses the electric drive subsystem as the core for power supply. This prevents over-discharge problems while ensuring the power performance of the vehicle's electric drive subsystem.

[0023] In one possible implementation, S101 specifically includes:

[0024] S1011: Collect the actual current of the power battery pack through message data. I Actual voltage U Maximum permissible charge and discharge current I p .

[0025] A data packet is a data unit used for exchanging and transmitting information in a network; it is a block of data that a station sends at one time. It contains complete data information and varies greatly in length, being unlimited and variable. A data packet includes not only the data to be transmitted but also necessary additional information. During transmission, the packet is continuously encapsulated into packets, frames, and groups for transmission.

[0026] S1012: Obtain the output power of the power generation module through a fuel cell or internal combustion engine generator set. E p .

[0027] S102: Calculate the allowable power and actual output power of the power battery pack using the power information.

[0028] Understandably, based on the obtained power information, calculating the allowable power and actual output power of the power battery pack can determine the difference between the allowable power and actual output power. This indicator can serve as the basis for subsequent iterative calculations. The allowable power limits the maximum power supply capacity of the entire power battery pack. Incorporating the allowable power parameter into subsequent calculations can effectively prevent over-discharge of the power battery pack and avoid potential damage to the power subsystem.

[0029] In one possible implementation, S102 specifically includes:

[0030] S1021: Calculate the allowable power of the power battery pack based on the power information. and the actual output power of the power battery pack :

[0031] .

[0032] S103: Perform a first-level iterative calculation on the allowable power and the actual output power of the power battery pack to obtain the target first-level iterative result.

[0033] The target first-level iteration result is an intermediate parameter value obtained in the first-level iteration calculation, which can be used as the basis for subsequent iteration calculations.

[0034] It should be noted that iterative calculation is a process of repeated feedback in order to achieve the final target result. Each repeated calculation of the allowable power and the actual output power of the power battery pack is called an iteration, and the result of each iteration will be used as the initial value for the next iteration.

[0035] In one possible implementation, S103 specifically includes:

[0036] S1031: Calculate the allowable power of the power battery pack and the actual output power of the power battery pack power difference between :

[0037] .

[0038] S1032: Iteration step size for calculating the power difference :

[0039] in, This represents the iteration coefficient.

[0040] The setting of the iteration coefficient directly affects the value of the entire iteration step, which in turn affects the final calculation result. Therefore, setting an appropriate iteration coefficient can enable the allowable power of the electric drive subsystem to quickly and accurately approximate the true value.

[0041] In practical applications, the value of the iteration coefficient can be set according to actual needs.

[0042] S1033: Determine the power difference Is it greater than the power difference threshold? .

[0043] It should be noted that setting the power difference threshold is a variable indicator of the difference between the actual output power and the allowable power of the power battery pack. Depending on the different power difference thresholds, the first-level iterative result of the allowable output power is calculated in different ways.

[0044] S1034: When the power difference is greater than the power difference threshold In this case, the first-order iterative result of calculating the allowable output power using Formula 4 is obtained. :

[0045] .

[0046] In one possible implementation, S103 further includes:

[0047] S1035: When the power difference is less than or equal to the power difference threshold In this case, the first-order iterative result of the allowable output power is calculated using Formula 5. :

[0048] .

[0049] In one possible implementation, S103 further includes:

[0050] S1036: Determine the magnitude between the two first-level iteration results of the allowed output power, and take the minimum value among the first-level iteration results of the allowed output power as the target first-level iteration result. :

[0051] .

[0052] It should be noted that in Formula 6 When the power difference is greater than the power difference threshold The first-level iteration result obtained under the given conditions When the power difference is less than or equal to the power difference threshold The first-level iteration result obtained under the condition is that the allowable power of the power battery pack is used as the first-level iteration result. Based on the different first-level iteration results obtained according to the power difference threshold, the minimum value of the two is taken as the target first-level iteration result and participates in the subsequent iteration calculation.

[0053] S104: Perform second-level iteration calculations based on the first-level iteration results of the target to obtain the second-level iteration results of the target.

[0054] It should be noted that the target first-level iteration result is the minimum value in the first-level iteration calculation. The second-level iteration calculation is based on the target first-level iteration result, which can ensure that the actual output power of the power battery pack meets the power demand of the whole vehicle to the greatest extent.

[0055] In one possible implementation, S104 specifically includes:

[0056] S1041: Calculate the first-level iteration result of the target. and the actual output power of the power battery pack Second power difference :

[0057] ;

[0058] S1042: Calculate the second power difference. Iteration step size :

[0059] in, K 2 represents the iteration coefficient;

[0060] S1043: Determine whether the second power difference is greater than the second power difference threshold. ;

[0061] S1044: When the second power difference is greater than the second power difference threshold In this case, the allowable output power is calculated using Formula 9:

[0062] .

[0063] In one possible implementation, S104 further includes:

[0064] S1045: When the second power difference is less than or equal to the second power difference threshold In this case, the allowable output power is calculated using Formula 10:

[0065] ;

[0066] S1046: Take the minimum value of the allowed output power as the target second-level iteration result. :

[0067] .

[0068] It should be noted that the entire second-level iterative calculation is based on the target first-level iterative result obtained from the first-level iterative calculation process. The target second-level iterative result obtained will be used as the final iterative result in the calculation of the allowable output power of the electric drive subsystem.

[0069] S105: Determine the driving state of the new energy vehicle, and calculate the final allowable output power of the electric drive subsystem based on the driving state and the target second-level iteration result, wherein the driving state includes electric state and regenerative braking state.

[0070] It is understandable that it is important to distinguish the driving states of new energy vehicles. During driving, new energy vehicles are mainly in electric mode and regenerative braking mode. In electric mode, the power supply battery pack supplies power to the electric drive subsystem. At this time, the new energy vehicle is in a state of consuming electrical energy. In regenerative braking mode, the new energy vehicle is in a state of deceleration due to manual braking. In the braking state, the power generation system works and is in a state of energy recovery. Calculating the final allowable output power of the electric drive subsystem according to different driving states in different ways can make the final result closer to the real value, rather than directly calculating it without regard to reality.

[0071] In one possible implementation, S105 specifically includes:

[0072] S1051: Determine the vehicle's driving status;

[0073] S1052: When the driving state is electric, the final allowable output power is determined by formula 12:

[0074] in, Ep This indicates the output power of the power generation module;

[0075] S1053: Output the maximum value between the final allowable output power and 0.

[0076] .

[0077] In one possible implementation, S105 further includes:

[0078] S1054: When the driving state is the regenerative braking state, the final allowable output power is determined by formula 14:

[0079] ;

[0080] S1055: Take the maximum value between the final allowable output power and 0 as the allowable output power of the electric drive subsystem. :

[0081] .

[0082] Understandably, allocating different allowable output power of the electric drive subsystem to different driving states of new energy vehicles puts the energy of the entire power subsystem in a dynamic power supply and adjustment process, making the entire power dynamic management system more intelligent and more effective in distributing the electrical energy of the entire power subsystem. This ensures the power performance of the electric drive subsystem while avoiding power waste in the entire power subsystem.

[0083] In this embodiment of the invention, by acquiring the power information of the power supply subsystem and employing a two-stage power iteration calculation method, different driving states of the new energy vehicle are distinguished, and the final allowable output power of the electric drive subsystem is calculated. Without needing to obtain the working status and power of each accessory, the allowable power of the electric drive subsystem is dynamically adjusted, fully utilizing the power of the power supply subsystem. This avoids the power waste caused by directly calibrating the power of the accessory subsystems and fully leverages the dynamic rationality and electro-regenerative performance of the electric drive subsystem, preventing over-discharge of the power battery pack. While improving the overall vehicle performance, this avoids the increased costs associated with adding numerous sensors to acquire power information from various parts of the accessory subsystems, thus enhancing the product's competitiveness.

[0084] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for dynamic power management of new energy vehicles, characterized in that, A power dynamic management system for new energy vehicles includes a power supply subsystem, an electric drive subsystem, and an accessory subsystem. The power supply subsystem includes a power battery pack and a power generation module. The electric drive subsystem and the accessory subsystem are both connected to the power supply subsystem. The electric drive subsystem is connected to the power battery pack. The power dynamic management method for the new energy vehicle includes: S101: Collect power information of the power subsystem, wherein the power information includes the actual current of the power battery pack. I Actual voltage U Maximum permissible charge and discharge current I p The output power of the power generation module E p ; S102: Calculate the allowable power and actual output power of the power battery pack using the power information; S103: Perform a first-level iterative calculation on the allowable power and the actual output power of the power battery pack to obtain the target first-level iterative result; S104: Perform second-level iteration calculations based on the first-level iteration results of the target to obtain the second-level iteration results of the target; S105: Determine the driving state of the new energy vehicle, and calculate the final allowable output power of the electric drive subsystem based on the driving state and the target second-level iteration result, wherein the driving state includes electric state and regenerative braking state; Specifically, S101 includes: S1011: Collect the actual current of the power battery pack through message data. I Actual voltage U Maximum permissible charge and discharge current I p ; S1012: Obtain the output power of the power generation module through a fuel cell or internal combustion engine generator set. E p ; Specifically, S102 includes: S1021: Calculate the allowable power of the power battery pack based on the power information. and the actual output power of the power battery pack : ； Specifically, S103 includes: S1031: Calculate the allowable power of the power battery pack and the actual output power of the power battery pack power difference between : ； S1032: Iteration step size for calculating the power difference : in, Represents the iteration coefficients; S1033: Determine the power difference Is it greater than the power difference threshold? ; S1034: When the power difference is greater than the power difference threshold In this case, the first-order iterative result of calculating the allowable output power using Formula 4 is obtained. : ； S1035: When the power difference is less than or equal to the power difference threshold In this case, the first-order iterative result of the allowable output power is calculated using Formula 5. : ； S1036: Determine the magnitude between the two first-level iteration results of the allowed output power, and take the minimum value among the first-level iteration results of the allowed output power as the target first-level iteration result. : ； Specifically, S104 includes: S1041: Calculate the first-level iteration result of the target. and the actual output power of the power battery pack Second power difference : ； S1042: Calculate the second power difference. Iteration step size : in, Represents the iteration coefficients; S1043: Determine whether the second power difference is greater than the second power difference threshold. ; S1044: When the second power difference is greater than the second power difference threshold In this case, the allowable output power is calculated using Formula 9: ； S1045: When the second power difference is less than or equal to the second power difference threshold In this case, the allowable output power is calculated using Formula 10: ； S1046: Take the minimum value of the allowed output power as the target second-level iteration result. : ； Specifically, S105 includes: S1051: Determine the vehicle's driving status; S1052: When the driving state is electric, the final allowable output power is determined by formula 12: in, This indicates the output power of the power generation module; S1053: Output the maximum value between the final allowable output power and 0. 。 2. The power dynamic management method according to claim 1, characterized in that, The S105 further includes: S1054: When the driving state is the regenerative braking state, the final allowable output power is determined by formula 14: ； S1055: Take the maximum value between the final allowable output power and 0 as the allowable output power of the electric drive subsystem. : 。

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