An improved parallel regenerative braking system for small battery electric vehicle

Electric vehicles (EVs) have the advantage of using both regenerative braking and mechanical braking to produce the necessary braking torque. Currently, vehicles use Anti-lock Braking Systems (ABS) which provide intermittent braking torque to the vehicle and thereby prevents skidding or slipping of the vehicle by ensuring pure rolling of the wheels. Regenerative braking on the other hand generates the necessary braking torque by converting the kinetic energy of the vehicle to electrical energy via the motor(s). To coordinate both braking systems, the conventional method involves the use of crisp logic controllers that depend on lookup tables containing the data about various aspects of the vehicle such as battery state of charge (SoC), brake pedal input etc., to enable co-operative control of both systems. This paper presents a combined implementation of both braking systems in electric vehicles using separate fuzzy controllers for both ABS and regenerative braking. The control scheme is implemented such that when regenerative braking is not capable of providing enough braking torque, braking will be one by ABS. Two fuzzy logic controllers have been used, one to implement regenerative braking and the other to implement mechanical braking via ABS. If such a control algorithm is used, the driver will not have to manually adjust the level of regenerative braking in the vehicle and such an approach ensures that the braking process of an EV is smooth, safe and efficient. It also reduces the wear and tear of the brake pads thereby extending their life and reducing the cost of maintenance and by extension the total cost of ownership of the vehicle. The results demonstrate that the controllers for both ABS and regenerative braking can coordinate efficiently and reliably to produce proper and safe braking of the vehicle.

When braking on wet roads, Antilock Braking System (ABS) control can be triggered because the available brake torque is not sufficient. When the ABS system is active, for a hybrid electric vehicle, the regenerative brake is switched off to safeguard the normal ABS function. When the ABS control is terminated, it would be favorable to reactivate the regenerative brake. However, recurring cycles from ABS to motor regenerative braking could occur. This condition is felt to be unpleasant by the driver and has adverse effects on driving stability. In this paper, a novel hybrid antiskid braking system using fuzzy logic is proposed for a hybrid electric vehicle that has a regenerative braking system operatively connected to an electric traction motor and a separate hydraulic braking system. This control strategy and the method for coordination between regenerative and hydraulic braking are developed. The motor regenerative braking controller is designed. Control of regenerative and hydraulic braking force distribution is investigated. The simulation and experimental results show that vehicle braking performance and fuel economy can be improved and the proposed control strategy and method are effective and robust.

Design of Hybrid Electric Vehicle Braking Control System with Target Wheel Slip Ratio Control

Anti-lock braking systems are essential for ensuring vehicle safety by regulating tyre slip and maintaining stability during braking. In electric vehicles, regenerative braking offers a unique opportunity to recover energy and enhance efficiency. However, the integration of regenerative and hydraulic braking systems introduces significant control challenges due to their differing dynamics. This paper presents a novel hierarchical control framework for a blended hydraulic–regenerative braking system, designed to optimise both safety and energy recovery during severe braking manoeuvres. A multi-level control architecture is proposed: the high-level controller coordinates torque distribution between hydraulic and regenerative braking; the mid-level employs sliding mode control for precise tyre slip regulation; and the low-level controller governs actuator dynamics. The system is modelled comprehensively, accounting for vehicle, tyre, and actuator characteristics, and is validated under various driving conditions. Results demonstrate that the proposed system maintains robust longitudinal slip control while significantly enhancing energy recovery, achieving a harmonious balance between braking performance, efficiency, and safety.

New Challenges for Brake and Modulation Systems in Hybrid Electric Vehicles (HEVs) and Electric Vehicles (EVs)

Electronic Braking System of EV And HEV---Integration of Regenerative Braking, Automatic Braking Force Control and ABS

Project the energy regenerative braking feedback lockup electromechanical integrated brake system for vehicles. Integrate EMB and friction brake system, and design the regenerative brake system, further choose the generator types respectively for the common gas engine car and electric car. Set up the system dynamic model. Based on the Matlab/Simulink, establish the simulation test system of the vehicles regenerative braking system. Using the simulation model for the Chery A3 car, we respectively simulate and analyse the braking and energy reusing performances of the low-brake strength and the high-brake strength regenerative braking models to the two brake systems. The study results indicate that the energy regenerative braking feedback lockup electromechanical integrated brake system for vehicles can satisfy the regenerative braking performance requirements of different vehicles according to the braking energy feedback quantity and the regenerative braking efficiency needed by the different vehicles, so the application is wider. The brake system does not only have higher regenerative braking efficiency, but also can guarantee the vehicles braking safety.

Design and performance analysis of braking system in an electric vehicle using adaptive neural networks

Most parallel hybrid electric vehicles (HEV) employ both a hydraulic braking system and a regenerative braking system to provide enhanced braking performance and energy regeneration. A new design of a combined braking control strategy (CBCS) is presented in this paper. The design is based on a new method of HEV braking torque distribution that makes the hydraulic braking system work together with the regenerative braking system. The control system meets the requirements of a vehicle longitudinal braking performance and gets more regenerative energy charge back to the battery. In the described system, a logic threshold control strategy (LTCS) is developed to adjust the hydraulic braking torque dynamically, and a fuzzy logic control strategy (FCS) is applied to adjust the regenerative braking torque dynamically. With the control strategy, the hydraulic braking system and the regenerative braking system work synchronously to assure high regenerative efficiency and good braking performance, even on roads with a low adhesion coefficient when emergency braking is required. The proposed braking control strategy is steady and effective, as demonstrated by the experiment and the simulation.

Urban bus has to start and stop frequently due to typical urban traffic conditions, which, however, can be put to good use by regenerative braking. Regenerative braking is a key technology which not only improves vehicle’s fuel economy in mild braking, but also ensures vehicle safety in emergency braking conditions. Because of the inherent limitations of traditional braking system in recycling energy, it is necessary to change its structure to decouple the brake pressure and the brake pedal force. To solve this problem, a compromise design combining traditional pneumatic braking system with brake-by-wire (BBW) system is adopted in this paper on parallel hybrid electric bus. With the transformed braking system, an efficient coordinated control strategy is proposed to solve the problem caused by the different response speeds of pneumatic braking and regenerative braking. The proposed control strategy is carried out, where the road condition varies and different control methods are adopted. Results show that the adopted braking system and the proposed coordinated control strategy are suitable for different roads, and effective in recovering energy and ensuring vehicle safety. At the same time, shorter braking distance and better control of slip ratio verify the performance of MPC compared with a logical threshold-based control. Therefore, this study may offer a useful theoretical reference to the choice of braking system and braking control strategy design in hybrid electric vehicle (HEV).

<div>The tailpipe zero-emission legislation has pushed the automotive industry toward more electrification. Regenerative braking is the capability of electric machines to provide brake torque. So far, the regenerative braking feature is primarily considered due to its effect on energy efficiency. However, using individual e-machines for each wheel makes it possible to apply the antilock braking function due to the fast torque-tracking characteristics of permanent magnet synchronous motors (PMSM). Due to its considerable cost reduction, in this article, a feasibility study is carried out to investigate if the ABS function can be done purely through regenerative braking using a mid-fidelity model-based approach. An uni-tire model of the vehicle with a surface-mount PMSM (SPMSM) model is used to verify the idea. The proposed ABS control system has a hierarchical structure containing a high-level longitudinal slip controller and a low-level SPMSM torque controller. Given the uncertainties of the tire–road dynamics, a sliding mode control method is designed and employed as a high-level slip controller. Also, a PID vector control method is used to keep the SPMSM braking torque at the optimal value requested by the high-level controller. Moreover, in order to estimate the tire longitudinal slip and vehicle velocity, an extended Kalman filter (EKF) is developed that estimates both parameters at the same time. The results show that the proposed hierarchical control and estimators can keep the tire longitudinal slip at the optimal value and prevent the wheel from locking in a variety of road conditions.</div>

With the development of the global automotive industry, environmental pollution and driving safety have been major problems. This paper focuses on a novel integrated cooperative antilock braking system (ABS) controller, which is used for antilock regenerative braking systems (ARBS) and antilock mechanical braking systems (AMBS) for hybrid electric vehicles (HEV) driving on different road surfaces. An intelligent tire system is utilized to detect varying road surfaces to obtain friction information and optimal operation slip ratio. In addition, the HEV eight‐degree‐of‐freedom dynamics model is developed for ABS control, which includes the LuGre tire model. Adaptive backstepping and finite state machine controllers are explored to maintain optimal wheel slip and regenerate energy, based on wheel slip, battery state of charge (SOC), motor capability torque, and vehicle velocity, and to develop the switching rules of regenerative and mechanical braking systems. In order to evaluate the performance of regenerative and mechanical braking systems on harvesting energy and driving safety, the HEV and LuGre dynamic tire models are developed in MATLAB SIMULINK /SimDriveline. The estimation results of different road surfaces and slip controller effects are tested via the experiments and simulations, finding good braking performances and high regenerative efficiency in different maneuvers.

Nowadays, the automobile systems like suspension, transmission, braking and clutch systems are controlled through the wire concept. To overcome the drawbacks of the existing conventional hydraulic braking system (CHB), magnetorheological brake (MRB) is introduced in this project. CHB require complex mechanical parts to dissipate energy. A magnetorheological fluid (MRF) brake is more efficient than conventional braking system in terms of weight reduction and response time. The research work is concerned with the development of a new braking system which employs MRF as working medium. MRB design proposed in earlier studies is to be further improved according to additional practical design criteria and constraints and more in-depth electromagnetic finite element analysis. The design procedure comprises the selection of materials for MRB, creating an analytical model for finding the braking torque produced by the MRB and finite element analysis of the MRB.

<div class="section abstract"><div class="htmlview paragraph">Any young person who has taken delight in playing with toy slot cars knows that the world of racing and the world of electric cars has been intertwined for a long time. And anyone who has driven a modern performance electric vehicle knows that the instant acceleration, exhilarating speeds, and joy of driving of slot cars is reflected in these full sized “toys”, with the many more practical benefits that come from being full-sized and steerable. There is strong foreshadowing of a vibrant future for performance cars in some of the EV’s on the market now and in the near future, some offering “ludicrous” acceleration, and others storied nameplates with performance to match. The ease at which powerful electric drives can capably hurtle a massive vehicle around the track at high speeds, combined with the potential for the same electric drives to exert powerful regenerative braking, creates a very interesting situation for brake engineers. What wins out in the end - raw power or regenerative braking? What can change in the course of a track session that would affect how braking energy is shared between the friction brake system and electric drives? How does this affect the brake system design and specification for a performance EV? This paper will walk through a design study to explore these questions, and in the course of doing so, will also explore some methodologies for engineering the brake systems for high performance EV’s that will include Driver In the Loop (DIL) simulations, brake system performance simulations, and inertia dynamometer testing, as well as “simple but sufficient” means of accounting for the drive and regenerative braking system behavior.</div></div>

Intelligent Sliding Mode Scheme for Regenerative Braking Control