Kinetic energy recovery control system

Abstract

The present invention relates to the technical field of electric vehicles, and in particular to a kinetic energy recovery control system, comprising a sensing module, an information processing module and a brake control execution module. The modules are connected via different types of buses, and the signal transmission between the modules is real-time. When the driver steps on the brake pedal in a normal driving state, the kinetic energy recovery function is first executed, and if necessary, the mechanical brake is executed to ensure that the vehicle can complete the braking process. The present invention uses a sensing module to obtain comprehensive information, and then uses the information processing module to determine whether the conditions for kinetic energy recovery are met, and at the same time calculates the most reasonable kinetic energy recovery intensity at the moment, and finally executes kinetic energy recovery control through the brake control execution module. The present invention can solve the problem of a bad driving experience for the driver due to unreasonable and non-intelligent kinetic energy recovery intensity settings, while further improving the kinetic energy recovery efficiency and increasing vehicle driving safety, and can also reduce the frequency of use of the mechanical brake system.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to a kinetic energy recovery control system. Background Art

[0002] With the rapid development of automobiles and the positive response of relevant national policies, electric vehicles currently have considerable future development prospects. However, there are still certain defects in the range of electric vehicles. Especially in cold seasons, the range of electric vehicles is greatly reduced.

[0003] To extend the range and improve energy efficiency of electric vehicles, kinetic energy recovery systems have been introduced. In traditional fuel-powered vehicles, braking generates heat, which is wasted. However, in electric vehicles, under certain driving conditions, such as downhill driving and braking, kinetic energy recovery systems can convert some of this energy into electricity, which is then stored in the battery, extending the battery's range. Furthermore, kinetic energy recovery systems can improve the energy efficiency of electric vehicles, reducing their reliance on external energy sources, thereby lowering operating costs and environmental impact.

[0004] Currently, the energy recovery intensity settings of most kinetic energy recovery control systems on the market are not reasonable and intelligent enough, and users need to manually adjust them in different usage scenarios. Occasionally, the excessive energy recovery intensity will give the driver a strong drag feeling, affecting the driving experience. Summary of the Invention

[0005] The purpose of the present invention is to provide a kinetic energy recovery control system, aiming to solve the technical problems of unreasonable and unintelligent braking intensity settings in existing electric vehicle kinetic energy recovery control systems.

[0006] To achieve the above objectives, the present invention provides a kinetic energy recovery control system, comprising a sensing module, an information processing module, and a brake control execution module. The sensing module, the information processing module, and the brake control execution module are connected via different types of buses, and signals between the modules are transmitted in real time.

[0007] The information processing module is responsible for determining whether the conditions for kinetic energy recovery are met. If so, it calculates the most reasonable kinetic energy recovery intensity based on the information output by the perception module and transmits it to the brake control execution module. The brake control execution module changes the brake pedal travel action mode and divides the pedal travel control into two parts. The first part will brake and decelerate at the most reasonable kinetic energy recovery intensity under the current working conditions, and the second part will intervene in the mechanical brake system to brake when further braking is required.

[0008] If the kinetic energy recovery conditions are not met, the kinetic energy recovery function will be turned off during braking and the mechanical brake system will be used directly for braking.

[0009] Among them, the perception module includes vehicle information perception, road surface perception, driving condition perception and dangerous condition perception. The vehicle information perception includes the acquisition of vehicle speed, vehicle weight, accelerator pedal depth, battery remaining power and battery temperature information; the road surface perception includes the perception of road surface smoothness and road surface inclination; the driving condition perception is the identification of the current driving state of the car, which is used to determine whether the car is in a frequent start-stop state or a normal driving state; the dangerous condition perception is to identify the surrounding environment of the current vehicle, and identify whether there are obstacles that endanger driving safety and require emergency braking.

[0010] Among them, the current vehicle status obtained by the whole vehicle information perception determines whether to start kinetic energy recovery. Kinetic energy recovery cannot be started when at least one of the following conditions exists: the vehicle speed is lower than a preset value, the vehicle is in a frequent start-stop state, the accelerator pedal is not completely released, the battery temperature is lower than a preset value, and the remaining battery power is higher than a preset value.

[0011] The road surface smoothness and inclination information acquired by the road surface sensing can influence the vehicle's driving state, affecting the kinetic energy recovery intensity output by the information processing module. Specifically, smoothness sensing is primarily used to avoid slippery conditions caused by rain or snow. In such conditions, the kinetic energy recovery intensity cannot be too high, as this can cause tire slippage due to a rapid decrease in vehicle speed, compromising driving safety. By detecting changes in the vehicle body angle, it can be determined whether the vehicle is currently traveling uphill, downhill, or on a flat road.

[0012] If the car is detected to be frequently starting and stopping, and the speed falls below a preset value, the kinetic energy recovery will be disabled. However, if the car's speed is detected to be consistently above a preset value over a period of time, it is considered normal driving and the kinetic energy recovery function will be enabled. This sensing of driving conditions can prevent the driver from experiencing discomfort due to excessive braking.

[0013] Among them, when the current car is in a dangerous driving scenario, the kinetic energy recovery intensity during braking will increase, and the mechanical braking system will be intervened at the same time to reduce the braking distance of the vehicle as much as possible.

[0014] Among them, when the vehicle decelerates without stopping, the optimal braking intensity calculated by the information processing module shall not exceed the maximum braking intensity. The maximum braking intensity is calculated using the following formula:

[0015]

[0016] Where Fz1 is the normal reaction force of the ground on the front wheel; L is the wheelbase; g is the acceleration due to gravity; b is the distance from the rear axle to the center of mass; m is the mass of the car; h g is the height of the center of mass; G is the gravity of the car;

[0017] At the same time, it must also be less than the current maximum ground adhesion coefficient, that is:

[0018]

[0019] Where z is the braking strength, z max For maximum strength; is the maximum ground adhesion coefficient.

[0020] The brake control execution module distributes the received braking intensity to the front and rear wheels, and the distribution satisfies the following formula:

[0021] Fu1+Fu2=zG

[0022]

[0023] Where Fu1 and Fu2 are the front and rear wheel braking forces; z is the braking intensity; G is the vehicle's gravity; a is the distance from the front axle to the vehicle's center of mass; b is the distance from the rear axle to the center of mass; h g is the height of the vehicle's center of mass.

[0024] The present invention provides a kinetic energy recovery control system, including a perception module, an information processing module and a brake control execution module. The modules are connected through different types of buses, and the signal transmission between the modules is real-time. When the driver steps on the brake pedal in a normal driving state, the kinetic energy recovery function is first executed, and if necessary, the mechanical brake is executed to ensure that the vehicle can complete the braking process. The present invention uses the perception module to obtain comprehensive information, and then uses the information processing module to determine whether the conditions for kinetic energy recovery are met, and at the same time calculates the most reasonable kinetic energy recovery intensity at the moment, and finally executes the kinetic energy recovery control through the brake control execution module. The present invention can solve the problem of a bad driving experience for the driver due to unreasonable and non-intelligent kinetic energy recovery intensity settings, while further improving the kinetic energy recovery efficiency and increasing the safety of vehicle driving. It can also reduce the frequency of use of the mechanical brake system and extend its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 It is a schematic diagram of the module structure of a kinetic energy recovery control system of the present invention.

[0027] Figure 2 It is a schematic diagram of the working process of a kinetic energy recovery control system of the present invention. DETAILED DESCRIPTION

[0028] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0029] See also Figure 1 The present invention proposes a kinetic energy recovery control system, which includes a perception module, an information processing module, and a brake control execution module. The perception module, the information processing module, and the brake control execution module are connected through different types of buses, and signals between the modules are transmitted in real time;

[0030] The information processing module is responsible for determining whether the conditions for kinetic energy recovery are met. If so, it calculates the most reasonable kinetic energy recovery intensity based on the information output by the perception module and transmits it to the brake control execution module. The brake control execution module changes the brake pedal travel action mode and divides the pedal travel control into two parts. The first part will brake and decelerate at the most reasonable kinetic energy recovery intensity under the current working conditions, and the second part will intervene in the mechanical brake system to brake when further braking is required.

[0031] If the kinetic energy recovery conditions are not met, the kinetic energy recovery function will be turned off during braking and the mechanical brake system will be used directly for braking.

[0032] Specifically, the sensing module includes vehicle information perception, road surface perception, driving condition perception, and hazardous condition perception. Vehicle information perception specifically includes current vehicle speed, vehicle weight, accelerator pedal depth, current battery temperature, remaining battery charge, and other information. This information is collected primarily to determine whether kinetic energy recovery conditions are met and to determine the intensity of kinetic energy recovery. Kinetic energy recovery only takes effect when a certain vehicle speed is reached, the driver does not depress the accelerator pedal, the battery temperature is above a preset value, and the battery charge is below a preset value. If one or more of these conditions are not met, the information processing module disables the kinetic energy recovery function. Vehicle speed and accelerator pedal depth are collected via sensors, while vehicle weight is set by the vehicle manufacturer. Battery temperature and remaining battery charge are collected via the battery management system.

[0033] Road surface perception primarily acquires information about the current tire speed and vehicle body tilt angle, primarily through wheel speed sensors and angle sensors. By collecting wheel speed information and detecting a mismatch between the tire speed and vehicle speed, the information processing module determines that the vehicle's tires are currently slipping. To prevent further slipping due to kinetic energy recovery, the kinetic energy recovery intensity is reduced. If the current vehicle body tilt angle is detected as a negative value, the vehicle is determined to be downhill, and the kinetic energy recovery intensity is increased. If the current vehicle body tilt angle is detected as a positive value, the vehicle is determined to be uphill, and the kinetic energy recovery intensity is reduced.

[0034] Driving Condition Sensing detects whether the vehicle is experiencing frequent starts and stops or normal driving over a period of time. If the vehicle's speed is low and below a preset value for a period of time, the information processing module determines that the vehicle is in a frequent start-stop state and disables the vehicle's kinetic energy recovery function. If the vehicle operates well over a period of time, with a speed above a preset value and uniform speed variations, the information processing module determines that the vehicle is in a normal driving state, and the kinetic energy recovery function operates normally in this state.

[0035] Dangerous condition perception mainly obtains the current surrounding environment information through radar sensors and cameras installed on the vehicle, which is used to detect obstacles around the current vehicle, so that the information processing module can determine whether emergency braking is required. If obstacles that affect safe driving are detected around the current vehicle, the information processing module will determine that the vehicle needs emergency braking. The output kinetic energy recovery intensity will increase, and the mechanical brake system will intervene in the braking process to ensure that the vehicle stops safely and smoothly.

[0036] The information processing module, comprising a central processing unit (CPU) and a graphics processing unit (GPU), is responsible for processing the information output by the perception module. It first determines whether the current vehicle operating state meets the kinetic energy recovery requirements. The GPU processes the image signals output by the camera. If the kinetic energy recovery requirements are met and driving safety is not compromised, the kinetic energy recovery system is activated. The information processing module then uses a control algorithm to weigh the various pieces of information and outputs a braking intensity control signal, which is transmitted to the brake control system in the brake control execution module. If the kinetic energy recovery requirements are not met, the kinetic energy recovery function is disabled and a mechanical braking signal is output to the brake control system.

[0037] The brake control execution module divides the brake pedal travel into two parts based on the braking intensity output by the information processing module. When the driver depresses the first part of the brake pedal, the kinetic energy recovery system activates. The motor controller generates electricity by applying a negative torque to the motor. The magnitude of the negative torque is related to the kinetic energy recovery intensity. This energy is then rectified by the inverter and stored in the battery, completing the vehicle deceleration and kinetic energy recovery process. If further braking is required, the mechanical brake system intervenes when the driver depresses the pedal deeper than a certain value. The simultaneous action of the two systems completes the braking process.

[0038] For detailed braking procedures, please refer to Figure 2 shown.

[0039] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of the rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A kinetic energy recovery control system, characterized in that: It includes a perception module, an information processing module and a brake control execution module. The perception module, the information processing module and the brake control execution module are connected through different types of buses, and the signals between the modules are transmitted in real time; The information processing module is responsible for determining whether the conditions for kinetic energy recovery are met. If so, it calculates the most reasonable kinetic energy recovery intensity based on the information output by the perception module and transmits it to the brake control execution module. The brake control execution module changes the brake pedal travel action mode and divides the pedal travel control into two parts. The first part will brake and decelerate at the most reasonable kinetic energy recovery intensity under the current working conditions, and the second part will intervene in the mechanical brake system to brake when further braking is required. The perception module includes vehicle information perception, road surface perception, driving condition perception, and dangerous condition perception. The vehicle information perception includes the acquisition of vehicle speed, vehicle weight, accelerator pedal depth, battery remaining power, and battery temperature information; the road surface perception includes the perception of road surface smoothness and road surface inclination; Driving condition perception is the identification of the current driving state of the vehicle, used to determine whether the vehicle is in a state of frequent start-stop or normal driving; dangerous condition perception is the identification of the surrounding environment of the current vehicle, identifying whether there are obstacles that endanger driving safety and require emergency braking; The current vehicle state acquired by the vehicle information sensing determines whether to activate kinetic energy recovery. Kinetic energy recovery cannot be activated when at least one of the following conditions exists: the vehicle speed is lower than a preset value, the vehicle is in a frequent start-stop state, the accelerator pedal is not fully released, the battery temperature is lower than a preset value, and the remaining battery charge is higher than a preset value; When the vehicle decelerates without stopping, the optimal braking intensity calculated by the information processing module must not exceed the maximum braking intensity. The maximum braking intensity is calculated using the following formula: ； In the formula is the normal reaction force of the ground on the front wheel; L is the wheelbase; g is the acceleration due to gravity; b is the distance from the rear axle to the center of mass; m is the mass of the car; is the height of the center of mass; G is the gravity of the car; At the same time, it must also be less than the current maximum ground adhesion coefficient, that is: ； Where z is the braking intensity, is the maximum braking intensity; is the maximum adhesion coefficient to the ground; The brake control execution module distributes the received braking intensity to the front and rear wheels, and the distribution satisfies the following formula: ； ； In the formula 、 is the braking force of the front and rear wheels; z is the braking intensity; G is the weight of the car; a is the distance from the front axle to the center of mass of the car, and b is the distance from the rear axle to the center of mass; is the height of the vehicle's center of mass; If the kinetic energy recovery conditions are not met, the kinetic energy recovery function will be turned off during braking and the mechanical brake system will be used directly for braking.

2. The kinetic energy recovery control system according to claim 1, characterized in that: The smoothness and inclination information of the road surface obtained by the road surface sensing can affect the driving state of the vehicle. Different driving states will affect the kinetic energy recovery intensity output by the information processing module.

3. The kinetic energy recovery control system according to claim 2, characterized in that: If it is detected that the car starts and stops frequently, when the vehicle speed is lower than the preset value, the kinetic energy recovery intensity will be turned off under this operating condition; and when it is detected that the car's speed changes evenly over a period of time and is greater than the preset value, it is regarded as a normal driving state, and the kinetic energy recovery function will be turned on.

4. The kinetic energy recovery control system according to claim 3, characterized in that: When the car is in a dangerous driving scenario, the intensity of kinetic energy recovery during braking will increase, and the mechanical braking system will be intervened at the same time to reduce the braking distance of the vehicle as much as possible.

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