Braking Of Electric Vehicle Research Articles

Research on ABS control strategy of cornering braking of electric vehicle with four in-wheel-motors

Research on ABS control strategy of cornering braking of electric vehicle with four in-wheel-motors

Friction Losses During Slip Conditions in Regenerative Braking of Electric Vehicles

The regenerative braking system (RBS) in electric vehicles (EVs) enhances its capability against internal combustion engines (ICE). Antilock braking system (ABS) is widely used in RBS because of its maneuverability and safety. One of the purposes of applying ABS is to avoid slippage. Slip on the braking process, especially hydraulic brakes, results in a difference in time to stop the wheels and the vehicle. It is avoided because it relies on friction between the tires and the road to stop transportation. Timing results showed that ABS with high frequency, above 30 Hz, tended to act like hydraulic brakes. Hydraulic brakes achieved the highest time difference, 8 seconds at 2250 rpm. It increased the distance of 350 m in slipping while the lowest time difference ABS 10 Hz owned, 0.1 seconds at the same rpm. Slips caused losses. These losses could be minimized with low-frequency ABS. It converted the friction between the wheels and the brakes into electrical energy instead of stopping the vehicle. As a result, the 10 Hz ABS had the highest potency stored despite the lowest performance.

Research on composite braking control strategy of battery electric vehicle based on road surface recognition

Concerning the issue of low energy recovery in composite braking of battery electric vehicles, a composite braking control strategy based on road recognition is proposed. The structure of the composite braking system of electric vehicles is analyzed, and the road surface identifier is designed by fuzzy algorithm to track the peak adhesion coefficient of the road surface to obtain the maximum brake braking force. In addition, fuzzy inference is used to modify the proportional coefficient of the motor braking force to the total braking force so as to maximize the energy recovery, and CRUISE and MATLAB are used for joint simulation analysis. The results show that the proposed control strategy not only ensures the safety and stability of the vehicle braking, but also has larger motor braking torque, smaller braking distance and shorter braking time. Under New European Driving Cycle(NEDC), Federal Test Procedure (FTP) and Extra Urban Driving Cycle (EUDC), the battery state of charge ( SOC) values are increased by 3.66%, 1.89%, and 0.85% respectively, and the energy recovery is increased by 169.7, 633.2, and 37.1 kJ respectively.

Single Pedal Control of Battery Electric Vehicle by Pedal Torque Demand With Dynamic Zero Position

Intelligent pedal control is a new development trend of vehicle intelligence, an important application of which is the single pedal control being the driving and braking inputs for energy management of battery electric vehicle. Usually, a constant pedal angle is used as the zero position that is a boundary between the driving and the braking. Based on the dynamic zero position that is a variable pedal angle depicting the direction switch point during pedal rotation, we show a single pedal control approach to operate the driving and the braking of battery electric vehicle, which can make full use of the pedal stroke and improve the control performance. Pedal torque demand is observed by a new pedal dynamics model that depicts the dynamic variation of pedal position. A nonlinear model predictive controller is designed to realize optimal-based energy management, satisfy dynamic demands, improve ride quality, and ensure wheel anti-slip safety. To validate the effect of the single pedal control approach, both simulations and real vehicle tests are carried out. The results illustrate that the energy consumption of single pedal control can be reduced than the dual pedal control in several representative driving cycles benefited from the more efficient use of regenerative braking.

Nonlinear Control Design for Regenerative and Hybrid Antilock Braking in Electric Vehicles

The use of regenerative braking and recent electrohydraulic or electromechanical brake-by-wire systems with enhanced dynamics enables improved antilock braking control performance in electric vehicles. However, the possible benefit is often limited by suboptimal control architectures with separate distributed controllers for electric motor (EM) and friction brake torque requests. Furthermore, oversimplifications in synthesis models for brake control design constrain the achievable performance. Instead, to date, threshold-based algorithms are widely used in modern production vehicles despite having been designed for slower hydraulic brake systems originally. To exploit the full potential, this work proposes a continuous nonlinear control design using input–output linearization for robust wheel speed tracking control. The design uses a unified controller for the redundant actuators. In addition, it explicitly considers drivetrain oscillations induced by regenerative braking using onboard EMs in the synthesis model. The stability for the resulting zero dynamics is shown through the Lyapunov analysis. The nonlinear controller is augmented by a subsequent control allocation for splitting the control effort on the redundant actuators. The allocation design ensures consistent control performance for both regenerative braking and hybrid braking while simultaneously aiming for high-energy recovery. The overall antilock braking control design is implemented in an electric test vehicle. Its tracking performance, disturbance attenuation, and robustness are experimentally validated through various emergency braking maneuvers on different road surfaces.

Friction-induced noise in drum brakes: finite-element modeling and experiments with special focus on damping

Brake squeal in friction brakes is a typical audible noise phenomenon in vehicles leading to high development and sometimes warranty costs for the suppliers. The friction forces generated during braking are responsible for self-excited vibrations in the audible frequency range starting from 1hbox { kHz}. In the past countermeasures against friction-induced vibrations are mostly investigated for disk brakes while the present study focuses on drum brakes. Damping is in the context of self-excited vibrations often one of the key measures. Nowadays recuperative braking in electric vehicles relieves the conventional friction brake. Due to safety reasons, electric vehicles need to possess at least a second independent brake system. Therefore, simpler drum brakes are on the rise again when developing brake systems. Compared to brake disks, where damping elements can hardly be implemented, the freely accessible drum surface and the brake shoes offer so far unused potential for applying passive damping measures. The present paper focuses on how damping measures influence the noise behavior of drum brakes. Industrial and non-industrial brake components are investigated in detail. Experimental as well as numerical procedures are used to assess damping and noise characteristics.

Control of BLDC motor and Regenerative Braking in Electric Vehicle

Abstract: With the rising economy, fuel demand also increases. In today's world, fossil fuels are the major contribution to meeting these demands. However, it is not going to be the same scenario in the next decades as the fossil fuels levels are depleting there is a need for an alternative fuel that will satisfy energy requirements and will be a sustainable source in coming years. In the automotive industry petrol and diesel have been major fuels in driving vehicles. Although electric vehicles are going to be replaced by IC engines. Electric vehicles have lower fuel costs as compared to internal combustion engines but because of limited charging stations vehicles are bound to drive within certain distances. With the implementation of regenerative braking in electric vehicles, it is possible to charge batteries when the vehicle is breaking and thus increasing driving distance. This paper presents a simulation of control of BLDC motor with regenerative braking. Keywords: Regenerative Braking, BLDC Motor, Bi-Directional DC-DC Converter, VSI, Electric Drives.

A Novel Anti-Saturation Model-Free Adaptive Control Algorithm and Its Application in the Electric Vehicle Braking Energy Recovery System

In this work, a novel anti-saturation model-free adaptive control (AS-MFAC) algorithm is proposed for the problem of pure electric vehicle’s braking energy recovery with the uncertain dynamic external factors. In the process of energy recovery during vehicle braking, actuator saturation and error accumulation occur due to various external conditions. In AS-MFAC, the non-linear dynamics of the vehicle braking energy recovery process is firstly linearized via a novel dynamical linearization technique with a time-varying parameter pseudo partial derivative (PPD). Then, by proposing the concept of the saturation parameter, the AS-MFAC controller is designed. Consequently, the stability and safety of the braking system are guaranteed while ensuring energy recovery. The major advantages of the AS-MFAC algorithm are that the controller uses only input and output data from the regenerative braking control system and this approach addresses the actuator saturation problem as well as provides a feasible solution. Moreover, the stability of the AS-MFAC algorithm is proven by rigorous mathematical theory and its effectiveness is verified by a series of experimental simulations. Remarkably, the proposed AS-MFAC controller has the property of symmetry since the controller structure and the corresponding parameter (time-varying PPD) estimator are both inferred based on the project algorithm. Consequently, the structures of the controller and the parameters of AS-MFAC have a symmetric similarity.

Regenerative Braking in Electric Vehicle Using Quadratic Gain Bidirectional Converter

The manuscript proposes a quadratic gain bidirectional converter (QGBC). The proposed converter is operated in two different stages—step-up (motoring) and step-down (regenerative braking)—which can be employed in electric vehicle (EV) applications. The converter is operated in the continuous inductor current mode (CICM). For regenerative braking (RB) of permanent magnet brushless DC (PMBLDC) motor, the self-inductance of the motor is exploiting to step up the back electromagnetic force (EMF) of the motor to extract the energy even at low rotor speed. The design parameters of the converter are selected as battery voltage V s = 48 V , output voltage V o = 200 V , output power P o = 1 kW , and switching frequency f s = 20 kHz . The design system is simulated using MATLAB/Simulink. Finally, a 1 kW prototype is developed for validation and performance analysis of the converter. The converter operates at maximum efficiency of 95% during step-up operation of the converter. A DSP microcontroller TMS320F28335 is used to control the switches of the converter in the experimental setup.

Prototype production and comparative analysis of high-speed flywheel energy storage systems during regenerative braking in hybrid and electric vehicles

In conventional EVs and HEVs, only a small part of the vehicle's kinetic energy can be usefully stored during deceleration. Generally, this storage process can be done by providing energy flow to the main battery of the vehicle. Since batteries work with a chemical reaction, they are not suitable for fast charging and discharging required for regenerative braking. In this case, a fast storage system is needed to store the regenerative braking energy in a short time. As a solution, the flywheel energy storage system (FESS) can be offered.In the literature, power transmission of vehicles with integrated FESS is provided by mechanical systems (CVT FESS). These systems are heavy, high cost, large volume, and occupy the rear axle of the vehicle.In the proposed system, a purely electrical power transmission is proposed to store the kinetic energy of the vehicle in FESS. In developed topology, the traction machine of the vehicle is also used as a generator, and the recuperation energy is stored in the electrically driven (M/G) FESS.As a result of the experimental studies, a minimum of 56% energy recovery efficiency was obtained. In addition, it has been shown that the developed system is 30% lighter, occupies 60% less space in volume, is at least 50% more cost-effective, maintenance-free, and has fewer moving parts compared to the CVT FESS.As a result, the addition of a fast-response secondary energy storage system to the electric vehicle battery contributes to the increase in efficiency.

Optimization and control of battery-flywheel compound energy storage system during an electric vehicle braking

Combining the advantages of battery’s high specific energy and flywheel system’s high specific power, synthetically considering the effects of non-linear time-varying factors such as battery’s state of charge (SOC), open circuit voltage (OCV) and heat loss as well as flywheel’s rotating speed and its motor characteristic, the mathematical models of a battery-flywheel compound energy storage system are established. Taking the recovered braking energy of the system as an objective, an energy optimization method based on GA is proposed to obtain the optimal electric braking torque and current distribution factor under different working conditions, which realizes the current distribution between the battery and the flywheel as well as the allocation between the mechanical braking torque and the electric braking torque. Simultaneously, a double neural networks-based adaptive PI vector control method is proposed to regulate the rotating speed of the flywheel motor. Research results demonstrate that using the proposed methods the overall recovered energy increases by 1.17times and the maximum charging current of the battery decreases by 42.27% compared with a single battery system, and the stability and robustness of the flywheel system are significantly improved, which provides theoretical and technical references for making the energy management plan of electric vehicles.

Research on Control Strategy of Hydraulic Regenerative Braking of Electrohydraulic Hybrid Electric Vehicles

The vehicle will generate an amount of current while the electric vehicle just starting to regeneratively brake. In order to avoid the impact of high current on the traction battery, a novel electrohydraulic hybrid electric vehicle has been proposed. The main power source is supplied by the electric drive system, and the hydraulic system performs the auxiliary drive system that fully exerts the advantages of the electric drive system and the hydraulic drive system. A proper regenerative braking control strategy is presented, and the control parameters are determined by the fuzzy optimization algorithm. The simulation analysis built the model through the united simulation of AMESim and MATLAB/Simulink. The results illustrated that the optimized control strategy can reduce battery consumption by 1.22% under NEDC-operating conditions.

Research and Implementation of Electric Vehicle Braking Energy Recovery System Based on Computer

The invention and application of automobiles have made important contributions to the development of human civilization. With the innovation of computer technology and the change of people’s understanding, the structure, driving system and working efficiency of automobiles are changing and improving. Today, more than 100 years later, cars are still an important means of transportation in people’s daily life. Automobile industry has played a great role in contemporary world economic activities, bringing convenience to people’s lives, increasing many employment opportunities and bringing huge wealth. It has become one of the pillar industries of world economic development. While automobiles have made great contributions to human civilization, the air pollution caused by automobile exhaust has seriously affected people’s living environment. Today’s cars on the market use two kinds of energy sources, petroleum fuel and electric energy. In order to solve the environmental problems and energy crisis brought by the development of automobile industry, electric vehicles are favored by governments of various countries and major automobile companies in the world. Because of its advantages of energy efficiency, wide sources of electric energy and environmental protection, an upsurge of developing electric vehicles has swept the world. Today, with the rapid development of electric vehicles, battery life has become a serious obstacle to their faster development. So as to improve the cruising range of electric cars, that is significant to increase the battery quality or energy density, which also greatly increases the cost of electric vehicles and is not conducive to the further promotion of electric vehicles. We can conduct in-depth research on improving the braking energy recovery and utilization rate of electric vehicles. From the perspective of environmental protection, electric vehicles have zero emissions. Even if the exhaust emissions from power plants and other power generation methods are included, the air pollution can still be greatly reduced. The requirements of society for sustainable development and its own advantages make electric vehicles the correct direction for the future development of automobile industry.

High-power graphene supercapacitors for the effective storage of regenerative energy during the braking and deceleration process in electric vehicles

The practical applicability of a high-power graphene supercapacitor as an effective primary and auxiliary energy storage system for storing regenerative energy from the braking and deceleration process in electric vehicles (EVs) is studied.

Design and Analysis of Electrical Braking Torque Limit Trajectory for Regenerative Braking in Electric Vehicles With PMSM Drive Systems

In this article, an electrical braking torque limit trajectory is designed to improve the regenerative braking of electric vehicles based on a regenerative power analysis. Even though electric motors generally regenerate electric energy from kinetic energy, the drive system dissipates electric energy under certain low-speed operation conditions. This phenomenon has been addressed in many previous works and most of them compensate for this power dissipation region by modifying the electrical braking torque limit trajectory of the motor. However, the torque limit trajectory has never been considered based on a regenerative power analysis even though an inaccurate torque limit trajectory causes energy loss to the drive system. In this article, the regenerative power analysis for two major kinds of permanent magnet synchronous motor is performed. Afterward, torque limit trajectories are set based on this analysis so that batteries in electric vehicles can harvest the maximum regenerative energy in any circumstance. To verify the analysis and proposed torque limit trajectories, simulations and experiments are performed.

Vehicle Stability Control with Four-Wheel Independent Braking, Drive and Steering on In-Wheel Motor-Driven Electric Vehicles

This paper presents a method to design a vehicle stability controller with four-wheel independent braking (4WIB), drive (4WID) and steering (4WIS) for electric vehicles (EVs) adopting in-wheel motor (IWM) system. To improve lateral stability and maneuverability of vehicles, a direct yaw moment control strategy is adopted. A control allocation method is adopted to distribute control yaw moment into tire forces, generated by 4WIB, 4WID and 4WIS. A set of variable weights in the control allocation method is introduced for the application of several actuator combinations. Simulation on a driving simulation tool, CarSim®, shows that the proposed vehicle stability controller is capable of enhancing lateral stability and maneuverability. From the simulation, the effects of actuator combinations on control performance are analyzed.

Thermal characteristics of a lithium‐ion battery used in a hybrid electric vehicle under various driving cycles

Lithium-ion battery is the most preferable type for hybrid electric vehicle due to their superior performance. The battery performances and safety factors are influenced by its operating temperature, hence it needs to be controlled carefully. Battery has a good performance at high temperature but this put it at risks of thermal runaway and explosion. This study presents a simulation model to predict battery's thermal behaviours during discharging and charging through regenerative braking in a series hybrid electric vehicle under various driving cycles. In total, five driving cycles are covered namely New European Driving Cycle (NEDC), Artemis cycle, Japanese 10–15 Mode cycle, FTP-75 cycle and worldwide harmonised light vehicles test procedure cycle. Validation of the model is performed using experimental results for NEDC cycle. Important results presented in this study focus on the battery temperature under different driving cycles and the impacts by considering thermal generation during charging process. Even though the temperature increase is relatively small, but the contribution of heat generation during charging is significant especially in an aggressive driving cycle. These results are very important in providing better understanding on the battery thermal behaviours so that a more effective battery management system can be developed (199/200).

Application of Multiple Unipolar Axial Eddy Current Brakes for Lightweight Electric Vehicle Braking

The braking system in a vehicle has the main role of slowing down the speed or stopping the moving vehicle. Compared to mechanical braking, which utilizes friction, non-contact braking has several advantages, including longer lifetime and less maintenance. One form of non-contact braking systems is the eddy current brake (ECB), an electric braking system that employs eddy currents to operate. This research focuses on the impact of magnetic field sources used in the ECB. In addition, the number of magnetic field sources is also observed. In order to achieve an ECB design that can be easily applied in any types of vehicles, including motorcycles and compact cars, a compact ECB design with an excellent braking torque is required. In this study, a compact design of the ECB is obtained by distributing the required braking torque from the disc brake into multiple electromagnets. Finite element method-based modeling has been performed to study ECB parameters, including the number of coil winding, the number of electromagnets, and the electric current. The results of this study show that the developed compact ECB could produce 93.66% of the torque required for braking.

Regenerative braking system modeling by fuzzy Q-Learning

The regeneration factor, that expresses the ratio between the energy recovered to the battery during braking and the total braking energy, is difficult to be measured from independent instruments. In this paper, a reinforcement learning (RL) method is used to adjust and improve a fuzzy logic model for regenerative braking (FLmRB) for modeling Electric Vehicles’ (EV) regenerative braking systems (RBSs). With the proposed approach, a specialist can infer the regeneration factor, by tuning the model for a specific EV using real data gathered from field tests, using as inputs, only variables measured from independent instruments, namely EV acceleration and jerk, and road inclination. The proposed approach was tested with real data sets of the Nissan Leaf EV. Twelve short-distance data sets in urban areas were collected to learn the regeneration factor, and two long-distance data sets in urban and sub-urban areas were used to validate the learned models. The results show that the learning method can successfully learn the regenerative braking factor improving the previously proposed FLmRB model approach which is based on manual design of the model.

Fabrication and empirical analysis of graphene dispersion/activated carbon on conductive networks in porous graphite felt supercapacitor

Supercapacitors are a promising candidate for the regenerative braking system due to their inherent fast charging and high-current/temperature tolerance capabilities. However, most supercapacitors suffer from high weight to capacitance ratio, which averts the use of supercapacitors in regenerative braking in electric vehicles. This research proposes a new lightweight supercapacitor electrode fabrication, which consists of networking conductive layers of graphene dispersion and activated carbon in porous graphite felt using conductive ink. The composite electrode showed a specific capacitance up to 170 F g−1, or 13 F g−1 from a completed device in type III deep eutectic solvent electrolyte, which gave the starting voltage of 2.3 V. The submersion fabrication alleviated the fabrication compare to brush method and production time was reduced to under 3 min of physical preparation.