Design and control method of motor wheel angle module distributed super capacitor energy storage system

Abstract

The application discloses a kind of electric wheel angle module distributed super capacitor energy storage system design and control method.Design content includes: whole vehicle architecture arrangement scheme design, electric wheel angle module execution system structure selection and parameter matching, super capacitor topology structure selection and parameter matching, super capacitor energy storage system electrical principle composition scheme and control method design.The electric wheel angle module distributed super capacitor energy storage system designed in the application adopts super capacitor+on-board power battery composite energy storage system, and uses distributed design to super capacitor and forms high integration system with electric wheel angle module, stores brake recovery energy and vibration recovery energy in vehicle driving process, and supplies energy for near-by steer-by-wire and brake-by-wire execution system.The method realizes the optimization matching of automobile power system and chassis system, reduces the performance requirement of power battery, provides backup energy system for chassis at the same time, promotes the development of self-energy storage chassis technology and improves system functional safety.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to a design and control method of a distributed supercapacitor energy storage system for an electric wheel angle module. Background Art

[0002] With the rapid development of modern technology and growing concern for environmental issues, the modern automotive industry is rapidly developing towards the "four modernizations" of electrification, intelligence, connectivity, and sharing. With the continuous advancement of wire-controlled chassis technology for intelligent electric vehicles, distributed drive vehicles have become a key research direction for new energy vehicles. Electric wheel angle modules, which replace traditional wheel-side structures, offer advantages such as high integration, short transmission chains, high transmission efficiency, and rapid and precise system response. They enable chassis modularization and active safety control, facilitating the implementation of L3 and higher-level autonomous driving technologies.

[0003] In addition, to cope with the frequent starting, stopping, and steering required in urban driving conditions, the onboard power battery needs to be frequently charged and discharged to meet the energy storage requirements of the braking and steering systems in the electric wheel angle module, as well as energy recovery. This will lead to fluctuations in the load conditions of the onboard power battery and frequent charging and discharging, which will cause efficiency losses in the entire power system, as well as battery heating and life degradation. At the same time, due to the low power density of current onboard power batteries on the market, the number of battery cells needs to be increased to meet the higher peak power requirements of electric vehicles under certain specific operating conditions, resulting in high battery system manufacturing costs and placing higher requirements on chassis space layout and lightweighting. Supercapacitors are energy storage components with low energy density but high power density. As physical batteries, they do not undergo internal chemical reactions during charging and discharging. Therefore, they have high charge and discharge efficiency, fast response speed, wide operating temperature range, and long service life. The number of charge and discharge cycles can reach over 100,000, and even up to 200,000. Ordinary lithium batteries begin to significantly degrade after 300-500 cycles. These advantages make supercapacitors more suitable as power supply and energy storage components for electric wheel angle modules than onboard power batteries. Therefore, adopting a supercapacitor + onboard power battery composite power supply solution and integrating the supercapacitor with the electric wheel angle module can reduce the matching cost and space occupied by the onboard power battery, simplify the wheel side structure design, and promote the modular design of the intelligent chassis. At the same time, the supercapacitor enables self-energy storage in the electric wheel angle module, serving as an energy backup in the event of a system failure, providing redundancy with the onboard power battery and improving vehicle driving safety.

[0004] In summary, the current automotive industry urgently needs a design and control method for a distributed supercapacitor energy storage system for electric wheel angle modules, which can provide a reference for the design and control of such an energy storage system that is highly integrated with electric wheel angle modules and supercapacitors. Summary of the Invention

[0005] The application aims to provide a design and control method of an electric wheel corner module distributed super capacitor energy storage system.

[0006] To achieve the above-mentioned purpose, the application provides a design and control method of an electric wheel corner module distributed super capacitor energy storage system, comprising:

[0007] a whole vehicle architecture arrangement scheme based on the electric wheel corner module distributed super capacitor energy storage system;

[0008] structure selection and parameter matching of a specific execution system in the electric wheel corner module based on the electric wheel corner module system composition and structure scheme and the whole vehicle performance index;

[0009] topology structure selection and parameter matching of the super capacitor (300) based on the power requirement of the specific execution system in the electric wheel corner module and the whole vehicle voltage architecture;

[0010] design of an electrical principle composition scheme and a control method of the electric wheel corner module distributed super capacitor energy storage system based on the vehicle working condition requirement and the system failure problem.

[0011] Optionally, the composition of the electric wheel corner module distributed super capacitor energy storage system comprises an electric wheel corner module, an on-board power battery and an electronic control unit.

[0012] Optionally, the composition of the electric wheel corner module comprises a first steering system (100), a drive motor (200), a super capacitor (300), a second steering system (400), a regenerative suspension damper (500), an electronic mechanical brake system (600) and a wheel (700).

[0013] The whole vehicle performance index comprises a 100 km braking distance, a steering system variable transmission ratio and a target damping characteristic curve.

[0014] Optionally, the specific execution system comprises the first steering system (100), the regenerative suspension damper (500) and the electronic mechanical brake system (600).

[0015] The topology structure refers to a composite power topology structure between the super capacitor (300) and the on-board power battery.

[0016] Optionally, the system failure problem comprises a super capacitor failure problem and an on-board power battery failure problem.

[0017] Optionally, the process of structure selection and parameter matching of the specific execution system in the electric wheel corner module based on the electric wheel corner module system composition and structure scheme and the whole vehicle performance index comprises:

[0018] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, matching calculations are performed on various performance parameters of the electronic mechanical brake execution motor, structural parameters of the ball screw, and structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600);

[0019] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance indicators, matching calculations are performed on various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100);

[0020] Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, various performance parameters of the energy-feeding suspension shock absorber damping motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500) are matched and calculated.

[0021] Optionally, based on the power requirements of the specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle, the process of selecting the topology structure and matching the parameters of the supercapacitor (300) includes:

[0022] Selecting a topology of the supercapacitor (300) based on the power requirements of a specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle;

[0023] Based on the power requirements of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topological structure of the supercapacitor (300), various parameters of the supercapacitor (300) are matched and calculated.

[0024] Optionally, based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the process of matching and calculating various performance parameters of the electronic mechanical brake execution motor, the structural parameters of the ball screw, and the structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600) includes:

[0025] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, the structural scheme of the electronic mechanical braking system (600) is selected;

[0026] Determining the size of the brake gap and the time value for eliminating the brake gap based on the structural scheme of the electronic mechanical brake system (600) and the performance index of the entire vehicle;

[0027] Determining the maximum clamping force required for braking based on the structural scheme of the electronic mechanical braking system (600) and the braking distance per 100 kilometers;

[0028] Based on the braking gap size, the time value for eliminating the braking gap and the maximum clamping force required for the braking, the average speed, the rated dynamic load and the maximum driving torque of the ball screw are determined, and the structural parameters of the ball screw are determined;

[0029] Determine the performance parameters of the electronic mechanical brake actuator motor based on the average speed, maximum driving torque and structural parameters of the ball screw, and complete the selection of the electronic mechanical brake actuator motor;

[0030] The transmission ratio of the reduction mechanism and the number of teeth of each gear are determined based on the performance parameters of the electronic mechanical brake actuator motor, the structural parameters of the ball screw and the structural scheme of the reduction mechanism.

[0031] Optionally, based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the process of matching and calculating various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100) includes:

[0032] Based on the electric wheel angle module system composition and structural scheme and the vehicle performance index, the first steering system (100) structural scheme selection is completed;

[0033] Determining the in-situ steering resistance torque, emergency braking torque, and return torque based on the first steering system (100) structural scheme and vehicle structural parameters;

[0034] Determining the rated torque of the steering motor of the first steering system and structural parameters of the ball screw based on the in-situ steering resistance torque, the emergency braking torque, and the aligning torque;

[0035] determining a rated speed of a steering motor of the first steering system based on the variable transmission ratio of the steering system and structural parameters of the ball screw;

[0036] Based on the rated torque and rated speed of the first steering system steering motor, performance parameters of the first steering system steering motor are determined to complete the selection of the first steering system steering motor.

[0037] Optionally, based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the process of matching and calculating various performance parameters of the energy-feeding suspension shock absorber damping motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500) includes:

[0038] Based on the system composition and structural scheme of the electric wheel angle module and the performance index of the whole vehicle, the structural scheme of the energy-feeding suspension shock absorber (500) is selected, and the working requirements of the vibration reduction motor of the energy-feeding suspension shock absorber are determined;

[0039] Determine the structural parameters of the ball screw, the maximum power and the maximum speed of the vibration reduction motor of the energy-regenerating suspension shock absorber based on the target damping characteristic curve and the working requirements of the vibration reduction motor of the energy-regenerating suspension shock absorber;

[0040] Determining a base speed ratio and an overload coefficient of the vibration damping motor of the energy-regenerating suspension shock absorber based on a target damping characteristic curve and a maximum power and a maximum speed of the vibration damping motor of the energy-regenerating suspension shock absorber;

[0041] Based on the maximum power, maximum speed, base speed ratio and overload coefficient of the energy-feeding suspension shock absorber vibration damping motor, the rated power and rated speed of the energy-feeding suspension shock absorber vibration damping motor are determined to complete the selection of the energy-feeding suspension shock absorber vibration damping motor.

[0042] Optionally, based on the power requirements of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topology of the supercapacitor (300), the process of matching and calculating various parameters of the supercapacitor (300) includes:

[0043] Determining the working requirements of the supercapacitor (300) based on the power requirements of the specific execution system in the electric wheel angle module and the vehicle architecture layout plan;

[0044] Determining the number of supercapacitors (300) connected in series and the voltage across both ends thereof based on the power requirements of a specific execution system in the electric wheel angle module and the topological structure of the supercapacitor (300);

[0045] Based on the power requirements of a specific execution system in the electric wheel angle module and the working requirements of the super capacitor (300), the number of super capacitors (300) connected in parallel and the overall capacity are determined.

[0046] Optionally, based on vehicle operating requirements and taking into account system failures, the process of designing the electrical principle and control method of the distributed supercapacitor energy storage system for the electric wheel angle module includes:

[0047] Based on the vehicle operating conditions and considering the system failure issues, various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module are determined;

[0048] Based on the various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module, the electrical principle and composition scheme of the distributed supercapacitor energy storage system of the electric wheel angle module is designed;

[0049] Based on the various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module and the electrical principle composition scheme, a control method of the distributed supercapacitor energy storage system of the electric wheel angle module is designed.

[0050] The technical achievements of the present invention are:

[0051] Based on the vehicle architecture layout scheme and vehicle performance indicators of the distributed supercapacitor energy storage system of the electric wheel angle module, the present invention performs structural selection and parameter matching on the specific execution system in the electric wheel angle module, and based on the power requirements of the specific execution system and the voltage architecture of the vehicle, performs topological structure selection and parameter matching on the supercapacitor; finally, based on the vehicle operating conditions and taking into account the system failure problem, the electrical principle composition scheme and control method design of the distributed supercapacitor energy storage system of the electric wheel angle module are completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0053] Figure 1 is a design flow chart in an embodiment of the present invention;

[0054] Figure 2 This is a layout diagram of the entire vehicle architecture in an embodiment of the present invention;

[0055] Figure 3 This is an axonometric view of the electric wheel angle module in an embodiment of the present invention;

[0056] Figure 4 This is a flow chart of parameter matching in an embodiment of the present invention;

[0057] Figure 5 This is a block diagram of the electrical principle in an embodiment of the present invention;

[0058] Figure 6 This is a control flow diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0059] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0060] like Figure 1 As shown in the figure, the design and control method of the distributed supercapacitor energy storage system of the electric wheel angle module of the present invention mainly includes the following four aspects:

[0061] ■Vehicle architecture layout based on distributed supercapacitor energy storage system for electric wheel angle modules;

[0062] ■ Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific actuator system in the electric wheel angle module are carried out;

[0063] ■ Based on the power requirements of the specific actuator system in the electric wheel angle module and the vehicle voltage architecture, the supercapacitor topology is selected and parameter matching is carried out;

[0064] ■Based on the vehicle operating conditions and taking into account system failure issues, the electrical principle composition scheme and control method of the distributed supercapacitor energy storage system of the electric wheel angle module are designed.

[0065] The details are as follows:

[0066] 1. Vehicle architecture layout scheme based on distributed supercapacitor energy storage system of electric wheel angle module:

[0067] like Figure 2 As shown, the vehicle architecture layout mainly consists of four sets of electric wheel angle modules, an on-board power battery, and an electronic control unit. The electric wheel angle modules and supercapacitors are highly integrated. The four electric wheel angle modules of the vehicle are connected to the electronic control unit through electrical signals. Under the control of the electronic control unit, the vehicle's chassis active control functions such as driving, braking, steering, and suspension are realized to meet the acceleration, deceleration, steering movement, and stable driving needs of the vehicle. At the same time, energy flow will interact between the electric wheel angle modules, supercapacitors, and on-board power batteries to meet the energy supply and storage functions of the vehicle.

[0068] 2. Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are carried out

[0069] Specific structure selection and parameter matching content and methods include:

[0070] (1) System composition and structural scheme based on electric wheel angle module

[0071] The electric wheel angle module comprises a first steering system (100), a drive motor (200), a super capacitor (300), a second steering system (400), a feed-back suspension shock absorber (500), an electronic mechanical braking system (600), and a wheel (700). The first steering system (100), the feed-back suspension shock absorber (500), and the electronic mechanical braking system (600) constitute a specific execution system.

[0072] The structural scheme of the electric wheel angle module is as follows Figure 3As shown, the first steering system (100) is a main steering system, connected to the steering knuckle through a steering rod, and realizes the steering function by means of rod steering; the driving motor (200) adopts a wheel-side drive form, and is connected to the hub flange of the wheel (700) through two constant velocity universal joints, and is used to provide a driving torque for the vehicle to travel; the second steering system (400) is an auxiliary steering system, connected to the chassis through a pin shaft at the top, the driving motor (200) is installed at the bottom by bolts, the first steering system (100) is installed on the side, and the energy-feeding suspension shock absorber ( 500), the second steering system (400) is a redundant system of the first steering system (100), and can realize the steering function by all-wheel steering; the energy-feeding suspension shock absorber (500) is installed at the upper cross arm, and the energy-feeding suspension shock absorber vibration reduction motor is used to provide the suspension damping force to realize the vibration energy recovery function, and the specific power transmission path and working mode of the second steering system (400) and the energy-feeding suspension shock absorber (500) are relatively complex and will not be elaborated here; the electronic mechanical braking system (600) is connected to the lug on the steering knuckle by bolts, and mainly undertakes the braking function of the vehicle.

[0073] (2) Parameter matching and selection design of distributed supercapacitor energy storage system for electric wheel angle module:

[0074] Based on the system composition and structural scheme of the electric wheel angle module and the performance indicators of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are performed, and based on the power requirements of the specific execution system and the voltage architecture of the whole vehicle, the topology selection and parameter matching of the super capacitor (300) are performed.

[0075] The parameter matching process is as follows Figure 4 shown.

[0076] (3) Based on the composition and structural scheme of the electric wheel angle module system and the performance index of the whole vehicle, the structure selection and parameter matching of the electronic mechanical braking system (600) in the specific execution system are performed.

[0077] The selected electronic mechanical brake system (600) is mainly composed of an electronic mechanical brake actuator motor, a ball screw, a speed reduction mechanism, and a brake caliper body. Among them, the electronic mechanical brake actuator motor serves as a power source and outputs a high-speed, low-torque force. The speed reduction mechanism outputs a low-speed, high-torque force through deceleration and torque increase. The ball screw converts the transmitted rotational motion into axial linear motion, pushing the brake pads in the brake caliper body to clamp the brake disc and complete the braking work. Its parameter matching design work mainly includes the following seven aspects:

[0078] A. Determine the size of the brake gap and the time value for eliminating the brake gap:

[0079] When the car is in normal driving and the electronic mechanical brake system (600) is not in operation, the gap between the left and right brake pads and the brake disc is called the brake clearance. The setting of the brake clearance should not be too large, otherwise it will take too long to eliminate the gap, making the brake response too slow. At the same time, the brake clearance should not be too small, otherwise it will easily lead to incomplete separation between the brake pad and the brake disc when the brake is released, resulting in dragging and affecting work efficiency. After determining the brake clearance, the high sensitivity requirement of the electronic mechanical brake system (600) should be considered, and a suitable brake clearance elimination time value should be designed. The brake clearance s should be selected. a and the time value t for eliminating the brake gap a .

[0080] B. Determine the maximum clamping force required when the electronic mechanical brake system (600) brakes:

[0081] According to the performance index S of the automobile's 100km braking distance 100 The maximum braking deceleration a can be calculated bmax , as shown in formula 1.1.

[0082]

[0083] in, is the braking system reaction time, u0 is the initial braking velocity, i.e. u0 = 100 km / h. The braking intensity z is calculated as shown in Equation 1.2, where g is the acceleration due to gravity.

[0084]

[0085] According to automobile theory, during braking, the load is transferred, and the ground normal force on the front wheel increases, which increases the front wheel adhesion limit. Therefore, the clamping force required to make the wheel (700) lock and slide is also higher. Therefore, the maximum clamping force required for the electronic mechanical brake system (600) during braking is calculated by selecting the case of front wheel locking. The ground braking force F Xb1 , the front wheel adhesion limit on this road surface And the maximum front wheel brake force F μ1 The calculation formula is shown in Equation 1.3-1.5.

[0086]

[0087] in, is the adhesion coefficient of the road, G is the gravity of the car under full load, b is the rear wheelbase, h g is the height of the vehicle's center of mass, μ is the friction coefficient between the brake pad and the brake disc, R discis the effective friction radius of the brake disc, r is the rolling radius of the wheel (700), F max The maximum clamping force required by the electronic mechanical brake system (600) when braking. At the same time, the maximum braking force of the front wheel, the ground braking force on the front wheel when the front wheel is locked, and the front wheel adhesion limit must meet Therefore, the simultaneous equations 1.3-1.5 can be used to calculate F max .

[0088] C. Calculate the average speed of the ball screw:

[0089] According to the brake clearance s determined above a and the time value t for eliminating the brake gap a , it can be calculated that the average axial moving speed of the ball screw nut when the braking clearance is eliminated is Initially select the ball screw lead L and calculate the average speed n of the ball screw a , as shown in formula 1.6.

[0090]

[0091] D. Check the rated dynamic load of the ball screw:

[0092] During normal driving of a car, most of the time it is in a low to medium intensity braking state. Considering the strength and size of the ball screw, two-thirds of the maximum clamping force required by the electronic mechanical braking system (600) during braking is taken as the average load Fa to calculate the rated dynamic load C. a The verification is calculated as shown in formula 1.7-1.8.

[0093]

[0094] Among them, K h is the life coefficient, K n is the speed coefficient (the value is 1.61), K F is the load factor, K H is the hardness influence coefficient.

[0095] E. Maximum driving torque of ball screw:

[0096] After completing the verification of the ball screw's rated dynamic load, the ball screw parameters can be selected and the various structural parameters can be determined to calculate the maximum driving torque T of the ball screw. max-s , calculated as shown in formula 1.9.

[0097]

[0098] Where P1 is the ball screw lead, η p It is the positive transmission efficiency of the ball screw under preload condition.

[0099] F. Selection of electronic mechanical brake actuator motor:

[0100] In order to reduce the clamping force on the driving torque of the electronic mechanical brake, it is necessary to arrange a reduction mechanism to work together. The initial transmission ratio is i * , the rated speed requirement of the electronic mechanical brake actuator motor can be calculated And the continuous stall torque required to meet the maximum clamping force condition As shown in formulas 1.10-1.11.

[0101]

[0102] Based on the above calculated initial values, the motor parameters for the electronic mechanical brake are selected and the performance parameters are determined.

[0103] G. Design of reduction mechanism:

[0104] Mainstream reduction mechanisms include cylindrical gear pairs, planetary gear mechanisms, and worm gear pairs, primarily used with rotary motors, as well as wedges and crank-connecting rod mechanisms, primarily used with linear motors. Since the electromechanical brake actuator motor used in this invention is a rotary motor, a two-stage planetary gear reducer is selected as the reduction solution discussed here. Based on the above calculation results and the performance parameters of the selected electromechanical brake actuator motor, the transmission ratio i of the two-stage planetary gear reducer is determined, as shown in Equations 1.12-1.13.

[0105]

[0106] Among them, T max-d is the motor's continuous stall torque, n e is the rated speed of the motor, Z S1 is the number of teeth of the first-stage sun gear, Z R1 is the number of teeth of the first-stage ring gear, Z S2 is the number of teeth on the secondary sun gear, Z R2 is the number of teeth on the secondary ring gear, and the number of teeth on the planetary gear is Z Pi It can be calculated by formula 1.14 (i=1, 2).

[0107]

[0108] By combining 1.12-1.14, the number of teeth on each gear of the two-stage planetary gear reducer can be determined, thus completing the selection and design of the reduction mechanism scheme.

[0109] (4) Based on the composition and structural scheme of the electric wheel angle module system and the performance index of the whole vehicle, the first steering system (100) in the specific execution system is structurally selected and parameter matched.

[0110] The selected first steering system (100) adopts a rod steering method and is mainly composed of a first steering system steering motor, a ball screw, a steering rod, and a steering knuckle. Among them, the first steering system steering motor serves as a power source, and the output rotational motion is converted into axial linear motion by the ball screw, and the steering knuckle is driven by the steering rod to complete the steering work. Its parameter matching design work mainly includes the following two aspects:

[0111] A. First steering system steering motor torque matching:

[0112] The steering motor of the first steering system should mainly consider the following three torque loads in terms of steering capability: ① the in-situ steering resistance torque; ② the braking torque of the wheel (700) around the steering kingpin generated by emergency braking, referred to as the emergency braking torque; and ③ the aligning torque. At the same time, considering the dangerous working conditions of the combined effects of various torques, a certain safety margin should be left in the parameter matching design of the selected steering motor.

[0113] ①Steering resistance torque: Steering resistance torque M s There is currently no accurate mathematical model to calculate

[0114] The formula that is more commonly used is based on experience, such as shown in Formula 2.1.

[0115]

[0116] Wherein, f is the sliding friction coefficient between the wheel (700) and the road surface; G is the total vertical load of the wheel (700); and P is the tire pressure. Since load transfer occurs during braking, the vertical force of the front wheel increases, and thus the rotation resistance torque increases, the corrected single-wheel rotation resistance torque M is ws As shown in formula 1.15, where F Xb1 and F Xb2 The ground braking forces of the front and rear wheels respectively.

[0117]

[0118] ② Emergency braking torque: When the vehicle is in emergency braking, it will generate an impact torque around the kingpin. Since electric vehicles using electric wheel angle modules do not have a steering trapezoid, they need to use the first steering system steering motor output torque in each wheel system to offset it. The emergency braking torque M of a single electric wheel angle module is wb As shown in formula 2.3, where K p The kingpin offset.

[0119]

[0120] ③Restoring torque: The restoring torque of the electric wheel angle module is mainly caused by the vehicle gravity and lateral force. In the case of considering the load transfer during braking, the restoring torque M wz is calculated as shown in equations 2.4-2.6.

[0121]

[0122] M wz2 = (rsin T + e cos T) F s cos U (2.5)

[0123] M wz = M wz1 + M wz2 (2.6)

[0124] Where M wz1 is the gravity restoring torque, M wz2 is the lateral force restoring torque, U is the kingpin inclination angle, T is the kingpin caster angle, W is the average steering angle of the left and right wheels (700), e is the tire scrub radius, and F s is the lateral force of the tire. The electric wheel angle module steering motor drives the steering tie rod through the ball screw, which drives the steering knuckle, thereby forming the rotation torque of the wheel (700) around the z-axis. This torque must meet the demand of the sum of the original steering resistance torque, the emergency braking torque, and the restoring torque. The calculation process is shown in equations 2.7-2.8.

[0125] F str L k = M ws + M wb + M wz (2.7)

[0126]

[0127] Where T e-str is the rated torque of the steering motor, F str is the axial force of the steering tie rod, L k is the vertical distance between the steering tie rod and the kingpin, P2 is the ball screw lead, and η p is the positive transmission efficiency of the ball screw under pre-tightening force. The matching selection of the ball screw is the same as above and is not expanded here. During vehicle steering, F str and L k also change in real time as the wheel (700) angle changes. Therefore, the above 2.7-2.8 are mainly used for the initial selection of the first steering system steering motor parameters. The subsequent check needs to establish a distributed steering system dynamics model in Adams or other motion simulation software to analyze the kinematic relationship between the components during steering, and to adjust the axial force Fstr real-time analysis.

[0128] B. The first steering system steering motor speed matching:

[0129] The first steering system steering motor speed should meet the demand for wheel (700) rotation speed when steering, while considering that the electric wheel angle module can realize the variable transmission ratio steering of the steering system. The first steering system steering motor speed n e-str The calculation process is shown in equations 2.9-2.11.

[0130]

[0131] v str = w p L k (2.10)

[0132]

[0133] where w p is the angular velocity of the wheel (700) when steering, w w is the steering wheel input speed, i w is the variable transmission ratio of the steering system, v str is the steering rod axial speed. Similarly, v str and L k Subsequent checks also require motion simulation software to analyze the real-time accurate values, which will not be described here.

[0134] After the rated speed and rated torque of the first steering system steering motor are known, the parameter matching and selection of the first steering system steering motor can be completed, and the performance parameters are determined.

[0135] (5) Based on the composition and structure scheme of the electric wheel angle module system and the vehicle performance indicators, the structure selection and parameter matching of the regenerative suspension shock absorber (500) in the specific execution system are carried out.

[0136] The selected energy-feeding suspension shock absorber (500) is mainly composed of an energy-feeding suspension shock absorber damping motor, a ball screw and a connecting mechanism. Among them, the reciprocating linear motion of the suspension is converted into rotational motion by the ball screw, driving the energy-feeding suspension shock absorber damping motor to generate electricity and recover vibration energy. To match the parameters of the energy-feeding suspension shock absorber damping motor, it is necessary to predetermine the speed and force range of its working time, that is, the target damping characteristic curve is known. However, since the energy-feeding suspension shock absorber damping motor is in a constant power characteristic after the rated speed, the torque decreases as the speed increases. If the performance parameters are matched with the full speed range of the damping curve, it will lead to excessive power demand and performance waste. Therefore, the performance parameters of the energy-feeding suspension shock absorber damping motor only need to meet the working requirements of general roads. At the same time, in order to protect the energy-feeding suspension shock absorber damping motor from being damaged, the maximum speed needs to be designed under extreme working conditions. Its parameter matching design work mainly includes the following two aspects:

[0137] A. Energy-regenerative suspension shock absorber motor power and speed matching:

[0138] A quarter model of the suspension is established, the target damping characteristic curve is input into the model, and the vehicle is simulated at a certain speed through each level of road surface to obtain the distribution of the relative motion speed of the energy-feeding suspension shock absorber (500) under each level of road surface. The maximum speed v in the speed distribution is selected. dam , substituted into the target damping characteristic curve to obtain the damping force F dam At this time, the working point on the curve is P, which is used as the parameter matching basis for the vibration reduction motor of the energy-regenerating suspension shock absorber working on general roads. The maximum power of the vibration reduction motor of the energy-regenerating suspension shock absorber is P dam As shown in formula 3.1.

[0139]

[0140] The maximum speed of the vibration damping motor of the energy-regenerating suspension shock absorber can be matched with the maximum value of the target damping curve speed range, or the maximum speed under special circumstances specified by the national standard for the shock absorber. The calculation process is shown in Formula 3.2.

[0141]

[0142] Among them, n max-dam is the maximum speed of the vibration damping motor of the energy-regenerating suspension shock absorber, v max-dam is the relative motion speed of the energy-feeding suspension shock absorber (500) under the corresponding extreme working condition, and P3 is the lead of the ball screw in the energy-feeding suspension shock absorber (500).

[0143] B. The base speed ratio of the vibration damper motor of the energy-regenerating suspension is matched with the overload coefficient:

[0144] After determining the maximum power and maximum speed of the energy feedback suspension damper, the base speed ratio i b and the overload coefficient λ are selected according to the target damping characteristic curve, so that the high efficiency area of the energy feedback suspension damper is distributed in the working area of the target damping characteristic curve corresponding to the general road surface. b After determining the base speed ratio i e-dam and the overload coefficient λ, the rated speed n max-dam , the maximum torque T e-dam and the rated torque T sc of the energy feedback suspension damper can be calculated, as shown in equations 3.3-3.6.

[0145]

[0146]

[0147] After calculating the above parameters, the power and speed matching parameters of the energy feedback suspension damper can be matched and selected to determine the performance parameters.

[0148] 3. Based on the power demand of the specific execution system in the electric wheel angle module and the vehicle voltage architecture, the super capacitor is selected and parameter matched in topology structure

[0149] The super capacitor (300) in the electric wheel angle module is mainly used to supply energy to the electronic mechanical brake execution motor and the first steering system steering motor, and its energy source mainly comes from three parts: vehicle-mounted power battery charging, brake energy recovery and energy feedback suspension damper (500) vibration energy recovery. When the state of charge SOC sc of the super capacitor (300) is ≤x%, the charging of the super capacitor (300) is completed by the vehicle-mounted power battery, brake energy recovery and energy feedback suspension damper (500) vibration energy recovery, and when the state of charge SOC sc of the super capacitor (300) is >x%, the vehicle-mounted power battery stops charging it, and only brake energy recovery and energy feedback suspension damper (500) vibration energy recovery charge the super capacitor (300), and the working power P sc of the super capacitor (300) is as shown in equation 4.1.

[0150] P sc = P b + P reg-b + P reg-d -P emb -P str (4.1)

[0151] Where P b is the charging power of the vehicle-mounted power battery to the super capacitor (300), and The x% can be 20-30%, P reg-b is the charging power of braking energy recovery, P reg-d is the charging power of the vibration energy recovery of the energy-feeding suspension shock absorber (500), P emb The working power of the motor for the electromechanical brake, P str is the working power of the steering motor of the first steering system. In the face of frequent starting and stopping in urban working conditions, the supercapacitor (300) needs to take on the work of charging and discharging at the same time. From the perspective of the internal energy of the supercapacitor (300), when P sc >0, the supercapacitor (300) is in a charging state as a whole, and when P sc When <0, the supercapacitor (300) is in a discharge state as a whole.

[0152] Specific structure selection and parameter matching content and methods include:

[0153] (1) Selection of supercapacitor (300) topology:

[0154] Typically, the design of various components of a vehicle is developed around the voltage architecture of the vehicle (usually the voltage of the on-board power battery). Based on the power requirements of the specific execution system in the electric wheel angle module for the supercapacitor (300) and the voltage architecture of the vehicle, a fully active topology is selected as the topology between the supercapacitor (300) and the on-board power battery.

[0155] The topology is as follows Figure 5 As shown in the figure, the on-board power battery and supercapacitor are each connected in series with a DC-DC converter (DC-DC1, DC-DC2), and then connected in parallel to the DC bus. This structure can achieve decoupling control of the on-board power battery and supercapacitor, making the bus voltage more stable, while also making the control strategy more flexible and more efficient.

[0156] (2) The number of supercapacitors (300) connected in series matches the voltage across both ends:

[0157] The supercapacitor (300) in the electric wheel angle module is connected in parallel with the vehicle power battery using a bidirectional DC-DC converter (DC-DC). The function of the DC-DC is to adjust the voltage between the supercapacitor (300) and the vehicle power battery. When the voltage ratio between the two approaches 1, the DC-DC efficiency is higher. Therefore, when matching the parameters of the voltage across the supercapacitor (300), it should be as close as possible to the vehicle power battery voltage U b The voltage across the supercapacitor (300) must not be greater than the voltage of the vehicle's power battery to prevent the supercapacitor (300) from reversely charging the vehicle's power battery during driving, thereby damaging the battery's health. The calculation process for the number of supercapacitors (300) connected in series and the voltage across the supercapacitor (300) is shown in equations 4.2-4.4.

[0158] U uc ≤U b (4.2)

[0159]

[0160] U uc =U uc-single n sc-s (4.4)

[0161] Among them, U uc is the voltage across the supercapacitor (300), U uc-single is the nominal voltage of the supercapacitor (300), n sc-s is the number of supercapacitors (300) connected in series.

[0162] (3) The number of supercapacitors (300) connected in parallel to match the overall capacity

[0163] Since the functional requirements of the supercapacitor (300) are mainly divided into two parts: the energy storage requirement for braking energy recovery and vibration energy recovery of the energy-feeding suspension shock absorber (500), and the energy supply requirement for supplying energy to the electronic mechanical brake actuator motor and the first steering system steering motor, the overall capacity requirement of the supercapacitor (300) must be considered from the two parts of ① energy storage requirement and ② energy supply requirement. The calculation process is as follows.

[0164]

[0165] E sc ≥max{E reg , E use}(4.6)

[0166]

[0167] Among them, E sc is the maximum energy that the supercapacitor (300) can provide or store, C sc is the overall capacity of the supercapacitor (300), C sc-single is the single capacity of supercapacitor (300), n sc-p is the number of supercapacitors (300) connected in parallel, V max and V min are respectively the maximum voltage and the minimum voltage of the supercapacitor (300) monomer.

[0168] ① Energy storage demand E reg

[0169] The overall capacity of the designed supercapacitor (300) must be sufficient to store the energy generated by braking energy recovery and vibration energy recovery during the process of deceleration of the vehicle from the highest speed to zero. The calculation process is shown in the formula.

[0170]

[0171] E reg-d =P e-dam t b (4.9)

[0172]

[0173] Among them, E reg-b is the energy generated by braking energy recovery, v max is the maximum speed of the vehicle, η reg Maximum braking energy recovery rate, E reg-d is the energy generated by vibration energy recovery, t b is the time it takes for the vehicle to decelerate from its maximum speed to zero. It is a safety factor to prevent energy overflow due to insufficient energy storage space of the super capacitor (300).

[0174] ②Energy demand E use

[0175] Since only when the supercapacitor (300) has a state of charge SOC sc When the vehicle power battery is less than or equal to x%, the supercapacitor (300) will be charged by the vehicle power battery. Considering that it takes a certain amount of time for the battery to charge the supercapacitor (300), and at the same time, when the energy recovery power of the driving motor (200) and the energy-feeding suspension shock absorber (500) is small due to the road conditions, or when the vehicle power battery cannot be charged due to a fault, or when the driving motor (200) and the energy-feeding suspension shock absorber (500) cannot perform energy recovery due to a fault, it is necessary to ensure that the remaining energy in the supercapacitor (300) at this time can meet the working requirements of the electronic mechanical braking system (600) and the first steering system (100), so that the vehicle can safely and reliably execute the braking and steering instructions until the vehicle stops. The calculation process is shown in the formula.

[0176]

[0177] Among them, P emb The average power of the electromechanical brake motor during the vehicle deceleration from the maximum speed to zero, P str is the steering motor power of the first steering system, t strThe working time of the first steering system (100) during the braking process. By combining the above formulas, the number of super capacitors (300) in series and parallel in the electric wheel angle module, the voltage at both ends and the overall capacity can be calculated, and the parameter selection of the super capacitor (300) can be completed.

[0178] 4. Based on the vehicle operating conditions and considering the system failure issues, determine the electrical principle and control method of the distributed supercapacitor energy storage system for the electric wheel angle module

[0179] (1) It has the following five functional scenarios:

[0180] Functional scenario 1: When the vehicle is in the pre-use stage, the on-board power battery only charges the supercapacitor (300) and does not supply energy to other systems. When the driver needs to use the vehicle, he will start the vehicle in advance through the mobile phone to prepare. This preparation stage is called the pre-use stage.

[0181] Functional scenario 2: Under normal circumstances, the vehicle power battery is mainly responsible for supplying energy to the drive motor (200), the second steering system steering motor and the energy-feeding suspension shock absorber damping motor. At the same time, when the supercapacitor (300) is charged to the state SOC sc ≤x%, the vehicle power battery charges the super capacitor (300), and when the super capacitor (300) has a charge state SOC sc When the value is greater than x%, the charging of the supercapacitor (300) is stopped. The supercapacitor (300) is mainly responsible for supplying energy to the electronic mechanical brake actuator motor and the first steering system steering motor, while storing energy generated by braking energy recovery and vibration energy recovery of the energy-feeding suspension shock absorber (500).

[0182] Functional scenario 3: When the supercapacitor (300) fails, the on-board power battery stops charging the supercapacitor (300), the supercapacitor (300) stops working, and the on-board power battery is responsible for supplying energy to all systems.

[0183] Functional scenario 4: When the vehicle power battery fails, the vehicle power battery stops working, and the supercapacitor (300) serves as an energy backup and is responsible for supplying energy to the electronic mechanical brake actuator motor and the first steering system steering motor, so that the vehicle stops safely and smoothly.

[0184] Functional scenario 5: If the driver has finished using the vehicle and there is still energy remaining in the supercapacitor (300), the supercapacitor (300) is controlled to slowly charge the vehicle power battery at a low rate current until there is no energy remaining in the supercapacitor (300). If there is no energy remaining in the supercapacitor (300), there is no need to charge the vehicle power battery.

[0185] (2) Specific electrical principle composition scheme:

[0186] Based on the multiple functional scenarios of the electric wheel angle module distributed supercapacitor energy storage system, the electrical principle composition scheme of the electric wheel angle module distributed supercapacitor energy storage system mainly consists of an on-board power battery, an on-board power battery management system (BMS), a supercapacitor, a supercapacitor management system (SCMS), a bidirectional DC-DC converter (DC-DC1, DC-DC2), a bidirectional DC-AC converter (DC-AC1, DC-AC2), a switch (S1, S2, S3), a unidirectional diode (D2, D3), an electronic control unit, an electronic mechanical brake actuator motor, a first steering system steering motor, a feed-back suspension shock absorber damping motor, a drive motor (200), and a second steering system steering motor, such as Figure 5 The working status of the distributed supercapacitor energy storage system of the electric wheel angle module in various functional scenarios is as follows:

[0187] Functional scenario 1: When the vehicle is in the pre-use stage, the electronic control unit transmits the working instructions of each module in the form of electrical signals through CAN communication, so that S1 is closed, DC-DC1 is in Boost mode, and DC-DC2 is in Buck mode. At this time, the motors of each system are not working and the power demand is zero. The current will flow from the on-board power battery to the supercapacitor in one direction. The electronic control unit monitors the supercapacitor SOC in real time. When the supercapacitor state of charge SOC sc When it reaches 100%, charging stops.

[0188] Functional scenario 2: Under normal circumstances, S1, S2, and S3 are always open, DC-DC1 is in Boost mode, and DC-DC2 is in alternating mode. At this time, the energy of the vehicle power battery mainly flows to the drive motor (200), the second steering system steering motor, and the energy-feeding suspension shock absorber damping motor, while the energy of the supercapacitor mainly flows to the electronic mechanical brake execution motor and the first steering system steering motor. Since D2 and D3 limit the one-way flow of energy, the energy generated by braking energy recovery and vibration energy recovery will flow to the supercapacitor. When the electronic control unit monitors the SOC sc When ≤x%, S1 is closed and the vehicle power battery will charge the supercapacitor until SOC sc Stop charging when >x%.

[0189] Functional scenario 3: When a supercapacitor fails, the supercapacitor management system SCMS in the supercapacitor will send a fault signal to the electronic control unit, which will control S1 to disconnect and S2 and S3 to close. At this time, the on-board power battery will no longer charge the supercapacitor and will be responsible for supplying energy to the motors of each system. At the same time, since the closure of S2 releases the restriction of D2 on the unidirectional flow of energy, the energy generated by braking energy recovery and vibration energy recovery will flow directly back to the on-board power battery.

[0190] Functional scenario 4: When the on-board power battery fails, the battery management system BMS in the on-board power battery will send a fault signal to the electronic control unit, and the electronic control unit will control S1 to disconnect. At this time, the on-board power battery stops working and does not supply energy to any system. The remaining energy stored in the supercapacitor will fully supply the electronic mechanical brake actuator motor and the first steering system steering motor to enable the vehicle to complete the necessary braking and steering work until the vehicle stops safely.

[0191] Functional scenario 5: When the driver finishes using the car, the supercapacitor management system SCMS will set the supercapacitor state of charge SOC sc Sent to the electronic control unit, the electronic control unit determines the SOC sc Is it zero? If SOC sc >0, the electronic control unit controls S1 to close, DC-DC1 is in Buck mode, DC-DC2 is in Boost mode, so that the energy in the supercapacitor slowly flows back to the vehicle power battery. If SOC sc =0, S1 is disconnected and charging stops.

[0192] (3) Based on the various functional scenarios of the electric wheel angle module distributed supercapacitor energy storage system and the electrical principle composition scheme, the specific process of the control method of the electric wheel angle module distributed supercapacitor energy storage system is as follows: Figure 6 shown.

[0193] The specific steps are as follows:

[0194] Step 0: Start;

[0195] Step 1: Determine whether the vehicle has entered the pre-start phase. If so, proceed to step 2; if not, proceed to step 14.

[0196] Step 2: S1 is closed, S2 and S3 are disconnected, DC-DC1 is in Boost mode, DC-DC2 is in Buck mode, and the on-board power battery supplies energy to the supercapacitor in one direction. Go to step 3.

[0197] Step 3: Determine whether the vehicle is faulty. If so, go to step 4; if not, go to step 7.

[0198] Step 4: Determine the cause of the fault. If it is a vehicle power battery fault, go to step 5. If it is a supercapacitor fault, go to step 6.

[0199] Step 5: S1, S2, and S3 are disconnected, DC-DC1 is not working, DC-DC2 is in alternating mode, the supercapacitor supplies energy to the electronic mechanical brake actuator motor and the first steering system steering motor, and step 11 is executed;

[0200] Step 6: S1 is open, S2 and S3 are closed, DC-DC1 is in alternating mode, DC-DC2 is not working, the on-board power battery supplies energy to the loads of each system, and then go to step 10;

[0201] Step 7: Determine the supercapacitor state of charge (SOC). If it is greater than x%, proceed to step 8. If it is greater than or equal to x%, proceed to step 9.

[0202] Step 8: S1, S2, and S3 are disconnected, DC-DC1 is in Boost mode, DC-DC2 is in alternating mode, and then go to step 10.

[0203] Step 9: S1 is closed, S2 and S3 are disconnected, DC-DC1 is in Boost mode, DC-DC2 is in alternating mode, and then go to step 10.

[0204] Step 10: Determine whether the vehicle is used. If so, proceed to step 11. If not, proceed to step 3.

[0205] Step 11: Brake until the vehicle stops, and then proceed to step 12;

[0206] Step 12: Determine the supercapacitor state of charge (SOC). If it is greater than 0, proceed to step 13. If it is equal to 0, proceed to step 14.

[0207] Step 13: S1 is closed, S2 and S3 are disconnected, DC-DC1 is in Buck mode, DC-DC2 is in Boost mode, and then go to step 12.

[0208] Step 14: End.

[0209] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. Design method of distributed supercapacitor energy storage system for electric wheel angle module, characterized by: include: The vehicle architecture layout based on the distributed supercapacitor energy storage system of the electric wheel angle module; Based on the system composition and structure of the electric wheel angle module and the performance index of the whole vehicle, the structure selection and parameter matching of the specific execution system in the electric wheel angle module are carried out, wherein the composition of the electric wheel angle module includes: a first steering system (100), a drive motor (200), a super capacitor (300), a second steering system (400), a feedback suspension shock absorber (500), an electronic mechanical braking system (600), and a wheel (700), wherein the first steering system is a main steering system, connected to the steering knuckle through a steering rod, and realizes the steering function by means of rod steering, and the second steering system is a secondary steering system, connected to the chassis through a pin shaft at the top, and the first steering system is installed on the side, which is a redundant system of the first steering system and can realize the steering function by means of all-wheel steering, and the super capacitor is mainly used for powering the electronic mechanical braking execution motor and the first steering system steering motor, and its energy source is mainly three parts: charging of the vehicle power battery, braking energy recovery and vibration energy recovery of the feedback suspension shock absorber, wherein the performance index of the whole vehicle includes: braking distance per 100 kilometers, variable transmission ratio of the steering system, and target damping characteristic curve; Based on the power requirements of the specific actuator system in the electric wheel angle module and the vehicle voltage architecture, the supercapacitor topology structure is selected and parameter matching is carried out. The specific actuator system consists of the first steering system, the regenerative suspension shock absorber, and the electronic mechanical braking system. The topology structure refers to the composite power supply topology between the supercapacitor and the on-board power battery. Based on the vehicle operating conditions and considering system failure issues, the electrical principle composition and control method of the distributed supercapacitor energy storage system of the electric wheel angle module are designed. The system failure issues include supercapacitor failure and vehicle power battery failure. Among them, the components of the distributed supercapacitor energy storage system of the electric wheel angle module include: an electric wheel angle module, an on-board power battery, and an electronic control unit.

2. The design method of the distributed supercapacitor energy storage system for electric wheel angle modules according to claim 1 is characterized in that: Based on the system composition and structure of the electric wheel angle module and the vehicle performance indicators, the process of selecting the structure and matching the parameters of the specific actuator system in the electric wheel angle module includes: Based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle, matching calculations are performed on various performance parameters of the electronic mechanical brake execution motor, structural parameters of the ball screw, and structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600); Based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle, matching calculation is performed on various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100); Based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle, various performance parameters of the energy-feeding suspension shock absorber damping motor and structural parameters of the ball screw in the energy-feeding suspension shock absorber (500) are matched and calculated.

3. The design method of the distributed supercapacitor energy storage system for electric wheel angle modules according to claim 1 is characterized in that: Based on the power requirements of the specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle, the process of selecting the topology structure and matching the parameters of the super capacitor (300) includes: Selecting a topology of the supercapacitor (300) based on the power requirements of a specific execution system in the electric wheel angle module and the voltage architecture of the entire vehicle; Based on the power requirements of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topological structure of the supercapacitor (300), various parameters of the supercapacitor (300) are matched and calculated.

4. The design method of the distributed supercapacitor energy storage system for the electric wheel angle module according to claim 2 is characterized in that: The process of matching and calculating various performance parameters of the electronic mechanical brake execution motor, the structural parameters of the ball screw, and the structural parameters of the speed reduction mechanism in the electronic mechanical brake system (600) based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle includes: Based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle, the structural selection of the electronic mechanical braking system (600) is completed; Determining the size of the brake gap and the time value for eliminating the brake gap based on the structure of the electronic mechanical brake system (600) and the performance index of the entire vehicle; Determining the maximum clamping force required for braking based on the structure of the electronic mechanical braking system (600) and a braking distance per 100 kilometers; Based on the braking gap size, the time value for eliminating the braking gap and the maximum clamping force required for the braking, the average speed, the rated dynamic load and the maximum driving torque of the ball screw are determined, and the structural parameters of the ball screw are determined; Determine the performance parameters of the electronic mechanical brake actuator motor based on the average speed, maximum driving torque and structural parameters of the ball screw, and complete the selection of the electronic mechanical brake actuator motor; The transmission ratio of the reduction mechanism and the number of teeth of each gear are determined based on the performance parameters of the electronic mechanical brake actuator motor, the structural parameters of the ball screw and the structure of the reduction mechanism.

5. The design method of the distributed supercapacitor energy storage system for electric wheel angle modules according to claim 2 is characterized in that: The process of matching and calculating various performance parameters of the first steering system steering motor and structural parameters of the ball screw in the first steering system (100) based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle includes: Based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle, the first steering system (100) is selected; Determining the in-situ steering resistance torque, emergency braking torque, and return torque based on the structure of the first steering system (100) and the structural parameters of the entire vehicle; Determining the rated torque of the steering motor of the first steering system and structural parameters of the ball screw based on the in-situ steering resistance torque, the emergency braking torque, and the aligning torque; determining a rated speed of a steering motor of the first steering system based on the variable transmission ratio of the steering system and structural parameters of the ball screw; Based on the rated torque and rated speed of the first steering system steering motor, performance parameters of the first steering system steering motor are determined to complete the selection of the first steering system steering motor.

6. The design method of the distributed supercapacitor energy storage system for electric wheel angle modules according to claim 2 is characterized in that: The process of matching and calculating various performance parameters of the energy-feeding suspension damper damping motor and structural parameters of the ball screw in the energy-feeding suspension damper (500) based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle comprises: Based on the composition and structure of the electric wheel angle module system and the performance index of the whole vehicle, the structural selection of the energy-feeding suspension shock absorber (500) is completed, and the working requirements of the vibration reduction motor of the energy-feeding suspension shock absorber are determined; Determine the structural parameters of the ball screw, the maximum power and the maximum speed of the vibration reduction motor of the energy-regenerating suspension shock absorber based on the target damping characteristic curve and the working requirements of the vibration reduction motor of the energy-regenerating suspension shock absorber; Determining a base speed ratio and an overload coefficient of the vibration damping motor of the energy-regenerating suspension shock absorber based on a target damping characteristic curve and a maximum power and a maximum speed of the vibration damping motor of the energy-regenerating suspension shock absorber; Based on the maximum power, maximum speed, base speed ratio and overload coefficient of the energy-feeding suspension shock absorber vibration damping motor, the rated power and rated speed of the energy-feeding suspension shock absorber vibration damping motor are determined to complete the selection of the energy-feeding suspension shock absorber vibration damping motor.

7. The design method of a distributed supercapacitor energy storage system for an electric wheel angle module according to claim 3 is characterized in that: The process of matching and calculating various parameters of the supercapacitor (300) based on the power requirements of the specific execution system in the electric wheel angle module, the voltage architecture of the entire vehicle, and the topology of the supercapacitor (300) includes: Determining the working requirements of the supercapacitor (300) based on the power requirements of the specific execution system in the electric wheel angle module and the overall vehicle architecture layout; Determining the number of supercapacitors (300) connected in series and the voltage across both ends thereof based on the power requirements of a specific execution system in the electric wheel angle module and the topological structure of the supercapacitor (300); Based on the power requirements of a specific execution system in the electric wheel angle module and the working requirements of the super capacitor (300), the number of super capacitors (300) connected in parallel and the overall capacity are determined.

8. The design method of a distributed supercapacitor energy storage system for an electric wheel angle module according to claim 1 is characterized in that: The process of designing the electrical principle composition and control method of the distributed supercapacitor energy storage system for the electric wheel angle module based on vehicle operating conditions and considering system failure issues includes: Based on the vehicle operating conditions and considering the system failure issues, various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module are determined; Based on the various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module, the electrical principle composition of the distributed supercapacitor energy storage system of the electric wheel angle module is designed; Based on the various functional scenarios of the distributed supercapacitor energy storage system of the electric wheel angle module and the electrical principle composition, a control method of the distributed supercapacitor energy storage system of the electric wheel angle module is designed.

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