Criteria

Text:
Display:

Results

Viewing 1 to 30 of 171
2014-09-28
Technical Paper
2014-01-2542
Liang Zhou, Chuqi Su
Abstract Recovering the braking energy and reusing it can significantly improve the fuel economy of hybrid electric vehicles (HEVs).The battery ability of recovering electricity limits the improvement of the regenerative braking performance. As one way to solve this problem, the technology of brake-by-wire can be adopted in the HEVs to use the recovery dynamically. The use of high-power electrical equipment, such as electromechanical brake (EMB), is working in the form of brake-by-wire. Due to the nature of EMB, there exists an obvious coupling relationship between the energy flow and brake force distribution. In this paper, a brake force distribution controller is proposed in HEV with EMB, which can maximize braking energy recovery, compared with the conventional distribution control without EMB. Meanwhile, an energy flow strategy working with the distribution controller is designed, which is less limited to the performance of the battery.
2014-09-28
Technical Paper
2014-01-2536
Alberto Boretti, Stefania Zanforlin
Abstract Real driving cycles are characterized by a sequence of accelerations, cruises, decelerations and engine idling. Recovering the braking energy is the most effective way to reduce the propulsive energy supply by the thermal engine. The fuel energy saving may be much larger than the propulsive energy saving because the ICE energy supply may be cut where the engine operates less efficiently and because the ICE can be made smaller. The present paper discusses the state of the art of hydro-pneumatic drivelines now becoming popular also for passenger cars and light duty vehicle applications permitting series and parallel hybrid operation. The papers presents the thermal engine operation when a passenger car fitted with the hydro-pneumatic hybrid driveline covers the hot new European driving cycle. From a reference fuel consumption of 4.71 liters/100 km with a traditional driveline, the fuel consumption reduces to 2.91 liters/100 km.
2014-09-28
Journal Article
2014-01-2538
Jongsung Kim, Chjhoon Jo, Yongsik Kwon, Jae Seung Cheon, Soung Jun Park, Gab Bae Jeon, Jaehun Shim
Abstract Electro-Mechanical Brake (EMB) is the brake system that is actuated by electrical energy and has a similar design with the Electric Parking Brake (EPB). It uses motor power and gears to provide the necessary torque and a screw & nut mechanism is used to convert the rotational movement into a translational one. The main difference of EMB compared with EPB is that the functional requirements of components are much higher to provide the necessary performance for service braking such as response time. Such highly responsive and independent brake actuators at each wheel lead to enhanced controllability which should result in not only better basic braking performance, but also improvements in various active braking functions such as integrated chassis control, driver assistance systems, or cooperative regenerative braking.
2014-09-28
Technical Paper
2014-01-2537
Zhizhong Wang, Liangyao Yu, Yufeng Wang, Kaihui Wu, Ning Pan, Jian Song, Liangxu Ma
Abstract The four-wheel-independent Electro-hydraulic Braking system (4WI EHB) is a wet type Brake-by-Wire system for passenger vehicle and is suitable for electric vehicle (EV) and hybrid electric vehicle (HEV) to cooperate with regenerative braking. This paper gives a review on the design concepts of the 4WI EHB from the following three aspects. 1. Hydraulic architectures. 2. Design concepts of the brake actuator. 3. Installation of the components on the vehicle. Simulations and experiments are carried out to further explore the performance of hydraulic backup and implicit hardware redundancy (IHR). A method to integrate the IHR with hydraulic backup without increasing the total amount of valves is proposed, making the IHR cost and weight competitive. By reviewing various design concepts and analyzing their advantages and drawbacks, a cost and weight competitive design concept of the 4WI EHB with good fail-safe and fault-tolerant performance is proposed.
2014-09-28
Technical Paper
2014-01-2541
Michael Herbert Putz, Christian Wunsch, Markus Schiffer, Jure Peternel
Abstract The electro-mechanical brake (EMB) of Vienna Engineering (VE) uses a highly non-linear mechanism to create the high pressing force of the pad. The advantage is that the pad moves very fast when the pad pressing force is low and moves slower with increasing pressing force. The normal force in EMBs is often controlled by observing mechanical deformation to conclude to stress or force, commonly using strain gauges. It causes costs of the gauge itself and attaching them to e.g. the caliper and a sensitive amplifier. The full gauge equipment goes into the safety-related brake control system. The faintest damage (e.g. stone impacts, heat) gets the vehicle to the repair shop making expensive replacement necessary. To avoid the costs of the force measurement in the safety related system VE took the electrical motor measurements from the very beginning of the brake development for EMB control.
2014-09-28
Technical Paper
2014-01-2539
Dongmei Wu, Haitao Ding, Konghui Guo, Yong Sun, Yang Li
Abstract Four-wheel-drive electric vehicles (4WD Evs) utilize in-wheel electric motors and Electro-Hydraulic Braking system (EHB). Then, all wheels torque can be controlled independently, and the braking pressure can be controlled more accurately and more fast than conventional braking system. Because of these advantages, 4WD Evs have potential applications in control engineering. In this paper, the in-wheel electric motors and EHB are applied as actuators in the vehicle stability control system. Based on the Direct Yaw-moment Control (DYC), the optimized wheel force distribution is given, and the coordination control of the hydraulic braking and the motor braking torque is considered. Then the EHB hardware-in-the-loop test bench is established in order to verify the effectiveness of the vehicle stability control algorithm through experiments.
2014-09-28
Technical Paper
2014-01-2531
Mandeep Singh Walia, Magnus Karlsson, Lars Hakansson, Gaurav Chopra
Abstract An analysis method to study the potentials of recovering the brake energy from Volvo articulated haulers has been developed. The study has been carried out with purpose to find out how and where possible hybrid solutions can be used. The method is based on the mapping of the peak brake power, brake energy and engine energy. This method was developed using adequate signals collected on haulers at three different customer sites. A conceptual study was also carried out concerning the brake energy to understand the actual amount of brake energy that may be stored in an Energy storage system (ESS). The results indicate that the analysis method developed can map the brake energy generated and also provide an overview of the actual amount of brake energy that can be accumulated in an ESS. Hence, the method may also providing guidelines regarding the selection of an ESS for a particular work site.
2014-04-01
Technical Paper
2014-01-0331
Masayuki Naito, Yasuhiro Koike, Shintaro Osaki, Shinichiro Morishita, Nanhao Quan
Abstract HEV and EV markets are in a rapid expansion tendency. Development of low-cost regenerative cooperation brake system is needed in order to respond to the consumers needs for HEV and EV. Regenerative cooperation brake system which HEV and EV are generally equipped with has stroke simulator. We developed simple composition brake system based on the conventional ESC unit without the stroke simulator, and our system realized a low-cost regenerative cooperation brake. The key technologies are the quiet pressurization control which can be used in the service application, which is to make brake force depending on brake travel, by gear pump and the master cylinder with idle stroke to realize regenerative cooperation brake. Thanks to the key technologies, both the high regenerative efficiency and the good service brake feeling were achieved.
2014-04-01
Technical Paper
2014-01-1717
Robert Lloyd
Abstract A hydro-mechanical transmission is described that approximates the “gearing” performance of a continuously variable transmission and incorporates all functions required for hydraulic regenerative braking. Other characteristics such as efficiency, noise, and responsiveness, match or exceed that of present day conventional automatic transmissions. Performance and physical sizing are shown for passenger vehicle, bus and truck transmissions.
2014-04-01
Technical Paper
2014-01-1740
Jiageng Ruan, Paul Walker
Abstract Regenerative braking energy recovery bears significance in extending the driving mileage of electric vehicles (EVs) while fulfilling real-time braking demands. Braking energy strategy plays a significant role in improving the regenerative braking performance and ensuring braking safety. This paper presents a regenerative braking energy recovery strategy for an example EV with a two-speed Dual Clutch Transmission (DCT). The two-speed DCT, with simple structure, can effectively extend the active vehicle speed-range for regenerative braking. Meanwhile, a shifting strategy is proposed for the DCT, working with the presented braking energy recovery strategy, to optimize the brake force distribution between front and rear wheels, motor and friction brake force. The EVs' model with the proposed regenerative braking strategy and the optimal shifting schedule was established and implemented in Matlab/Simulink.
2014-04-01
Technical Paper
2014-01-0267
Zhiting Zhu, Lu Xiong, Chi Jin
Abstract The control in transient conditions when hydraulic brake and regenerative brake switch mutually is the key technical issue about electric vehicle hybrid brake system, which has a direct influence on the braking feel of driver and vehicle braking comfort. A coordination control system has been proposed, including brake force distribution correction module and motor force compensation module. Brake force distribution correction module has fixed the distribution results in hydraulic brake force intervention condition, hydraulic brake force evacuation condition and regenerative brake force low speed evacuation condition. Motor compensation module has compensated hydraulic system with motor system, which has fast and accurate response, thus the response of whole hybrid system has been improved.
2014-04-01
Technical Paper
2014-01-1878
Li Sun, Mohamed Awadallah, Lianhua Chi, Nong Zhang
Abstract This paper presents a smart electric scooter system consisting of a microprocessor based vehicle controller (integrating an embedded regenerative braking controller), a 300W Permanent Magnet (PM) DC motor, two low-power DC-DC converters to form a higher power DC-DC converter pack, a motor controller, a supercapacitor bank and a capacitor cell balancing sub-system.
2014-04-01
Technical Paper
2014-01-1908
Rong He, Hongyu Zheng, Changfu Zong
Abstract In order to improve the braking energy recovery and ensure the braking comfort, a new type of regenerative braking coordinated control algorithm is designed in this paper. The hierarchical control theory is used to the regenerative braking control algorithm. First, the front axle braking force and rear axle braking force are distributed. Then the rear axle motor braking force and mechanical braking force are distributed. Finally, the dynamic coordinated control strategy is designed to control pneumatic braking system and motor braking system. Aimed at keeping the fluctuation of the total braking force of friction and the regenerative braking force small during braking modes switch, a coordinated controller was designed to control the pneumatic braking system to compensate the error of the motor braking force. Based on Matlab/Simulink platform, a parallel hybrid electric bus simulation model with electric braking system (EBS) was established.
2014-04-01
Technical Paper
2014-01-1864
Takao Suenaga, Takahiro Jo
Abstract The automotive industry is placing high importance on technologies that can reduce CO2, even in a highly fuel-efficient compact car. One major technology is Stop & Start(S&S) System, with a combined energy regeneration system. A key component of the system is a power supply storage device that has high-charge acceptance, light weight, and compact size. We believe a Lithium-ion (Li-ion) battery completely meets these requirements. For the battery, there are three key points: 1 Battery cell specification2 State Of Charge (SOC) detection method3 Temperature management for Li-ion battery. We have already proposed the battery cell and the SOC detection during SAE 2013, and now we are going to introduce “Temperature Management”. If the temperature of a Li-ion battery operates over 60 degrees Celsius, the battery could be severely damaged. Therefore, temperature management of the battery is very important.
2014-04-01
Technical Paper
2014-01-1727
James Gramling
Abstract It is very important to note that most present-day CVT's drive with a friction element. Unlike gears that can be produced with any size necessary for the torque load they must transfer, CVT's are limited in torque capacity and are only marginally suitable for small vehicle applications. A system is described using two variable-inertia flywheels to not only supply the heavy torque requirements during acceleration of a vehicle but also operate in reverse capturing the otherwise wasted decelerating torque (I.E. braking torque). This system (called Kinetic Energy Power Transmission System or KEPTS) provides all of the documented benefits of the use of an IVT for motor vehicle acceleration and also incorporates regenerative braking.
2014-04-01
Technical Paper
2014-01-1791
Chen Lv, Junzhi Zhang, Yutong Li, Ye Yuan
Abstract Regenerative braking, which can effectively improve vehicle's fuel economy by recuperating the kinetic energy during deceleration processes, has been applied in various types of electrified vehicle as one of its key technologies. To achieve high regeneration efficiency and also guarantee vehicle's brake safety, the regenerative brake should be coordinated with the mechanical brake. Therefore, the regenerative braking control performance can be significantly affected by the structure of mechanical braking system and the brake blending control strategy. By-wire brake system, which mechanically decouples the brake pedal from the hydraulic brake circuits, can make the braking force modulation more flexible. Moreover, its inherent characteristic of ‘pedal-decouple’ makes it well suited for the implementation in the cooperative regenerative braking control of electrified vehicles.
2014-04-01
Journal Article
2014-01-0110
Haohua Hong, Lifu Wang, Minyi Zheng, Nong Zhang
This paper employs the motion-mode energy method (MEM) to investigate the effects of a roll-plane hydraulically interconnected suspension (HIS) system on vehicle body-wheel motion-mode energy distribution. A roll-plane HIS system can directly provide stiffness and damping to vehicle roll motion-mode, in addition to spring and shock absorbers in each wheel station. A four degree-of-freedom (DOF) roll-plane half-car model is employed for this study, which contains four body-wheel motion-modes, including body bounce mode, body roll mode, wheel bounce mode and wheel roll mode. For a half-car model, its dynamic energy contained in the relative motions between its body and wheels is a sum of the energy of these four motion-modes. Numerical examples and full-car experiments are used to illustrate the concept of the effects of HIS on motion-mode energy distribution.
2013-11-27
Technical Paper
2013-01-2872
Alberto Boretti
Kinetic energy recovery systems (KERS) placed on one axle coupled to a traditional thermal engine on the other axle is possibly the best solution presently available to dramatically improve the fuel economy while providing better performances within strict budget constraints. Different KERS may be built purely electric, purely mechanic, or hybrid mechanic/electric differing for round trip efficiency, packaging, weights, costs and requirement of further research and development. The paper presents an experimental analysis of the energy flow to and from the battery of a latest Nissan Leaf covering the Urban Dynamometer Driving Schedule (UDDS). This analysis provides a state-of-the-art benchmark of the propulsion and regenerative braking efficiencies of electric vehicles with off-the-shelve technologies.
2013-10-15
Technical Paper
2013-32-9006
Takahiro Noyori, Setsuko Komada, Hirobumi Awakawa
Our new technology, the first technology in the small vehicle industry, achieves the fuel economy improvement due to the electricity through the highly efficient electricity generation and charge by the regenerative braking energy obtained during vehicle decelerating or coasting. The newly developed technologies is the regenerative braking system, which minimizes electricity generation during vehicle driving, while maximizes it during vehicle decelerating or coasting. Regenerative braking is the function to generate electric power using with the regenerative braking energy obtained during vehicle decelerating or coasting through the accelerator pedal released or the brake pedal applied. The kinetic energy from the vehicle in motion is recaptured as the electric power to be used for the electric component operation.
2013-10-14
Technical Paper
2013-01-2543
Satya Kaul, Jaideep Gupta, Shubham Sharma, Naveen Kumar
It is of common knowledge that tapping all the feasible sources of energy and systems which prevent losses is the need of the hour. Currently, many such systems have been developed including “REGENERATIVE BRAKING”. The usual method for regenerative braking includes using a dynamo attached to the crankshaft which gets charged when the wheel rotates during idling. However, this study aims at doing this differently by attaching the regenerative system at the wheels. Considering an example of wastage of energy, a 1000 kg car brakes from 36km/h (10m/s) to 18km/h (5m/s) about 150 times in a liter consumption of diesel. We can safely calculate wastage of 5625 KJ of kinetic energy. This paper aims to explore this immense potential source of energy recovery by producing & storing electricity using magnetic braking on wheels of automobiles.
2013-10-07
Technical Paper
2013-36-0404
Fabio Mazzariol Santiciolli, Jony Javorski Eckert, Eduardo Dos Santos Costa, Heron José Dionísio, Franco Giuseppe Dedini
The purpose of this paper is evaluating the amount of kinetic energy available to be regenerated by a hybrid electric vehicle (HEV) undergoing the Brazilian standardized driving cycle. Improvements on energy efficiency of the cars has become an urgent target of the Brazilian industry since Brazil launched a new automotive regulation imposing the reduction of 15.5% on the fuel consumption of the vehicles to be sold in this country in 2017 comparing to 2011. The HEVs are a possible solution for this situation. They are widely known by the high efficiency, mainly the ones capable to make the regenerative breaking, rescuing an already paid energy. Before the launch of HEVs in Brazil, the feasibility of these vehicles has to be accurately studied and one aspect to be evaluated is how much energy is possible to be rescued in the Brazilian standardized driving cycle.
2013-09-30
Technical Paper
2013-01-2065
Rayad Kubaisi, Konrad Herold, Frank Gauterin, Martin Giessler
Electric driven Vehicles (EV) can help reduce CO2 emissions caused by traffic. High acquisition costs and the limited driving range of electric vehicles are their major drawbacks. In the last few years many efforts in research have been made to increase the usability of EV's. A Battery Electric Vehicle (BEV) consists mainly of an electric motor and a battery. Both components allow regenerative braking, where kinetic energy can be transformed back to electric energy and stored in the battery during braking. Several types of Regenerative Braking Systems (RBS) already exist. These systems differentiate from each other by the concepts and strategies used, and therefore have different potential to increase the driving range of electric driven vehicles. Furthermore, the potential depends on the actual traffic situation and the actual state of the vehicle components.
2013-09-30
Journal Article
2013-01-2064
John Robinson, Tarunraj Singh
Linked front and rear braking systems are difficult to implement properly on motorcycles due to the large changes in wheel loading under braking. At the braking limit, there is little to no load on the rear wheel and any brake torque could lock it, making the vehicle laterally unstable. Therefore, most motorcycles have independent controls for the front and rear brakes, requiring the rider to balance the brake force distribution. Electric motorcycles have the ability to utilize the drive motor to apply braking torque at the rear wheel. In this paper a control technique has been developed to link rear wheel braking torque to the front brake lever without risking rear tire lock. Thereby, it is also possible to recapture the energy from rear wheel braking. The control strategy has been tested on a transient pitch model, with rotating wheels and tire model data.
2013-09-24
Technical Paper
2013-01-2396
Mohamed H. Zaher, Sabri Cetinkunt
This paper focuses on embedded control of a hybrid powertrain concepts for mobile vehicle applications. Optimal robust control approach is used to develop a real time energy management strategy. The main idea is to store the normally wasted mechanical regenerative energy in energy storage devices for later usage. The regenerative energy recovery opportunity exists in any condition where the speed of motion is in the opposite direction to the applied force or torque. This is the case when the vehicle is braking, decelerating, the motion is driven by gravitational force, or load driven. A rule based control algorithm is developed and is tuned for different work cycles and might be linked to a gain scheduling algorithm. A gain scheduling algorithm identifies the cycle being performed by the work-machine and its position via GPS, and maps both of them to the gains.
2013-04-08
Journal Article
2013-01-1466
Kerem Bayar, Ryan McGee, Hai Yu, Dale Crombez
This study presents the utilization of the hardware-in-the-loop (HIL) approach for regenerative braking (regen) control enhancement efforts for the power split hybrid vehicle architecture. The HIL stand used in this study includes a production brake control module along with the hydraulic brake system, constituted of an accelerator/brake pedal assembly, electric vacuum booster and pump, brake hydraulic circuit and four brake calipers. This work presents the validation of this HIL simulator with real vehicle data, during mild and heavy braking. Then by using the HIL approach, regen control is enhanced, specifically for two cases. The first case is the jerk in deceleration caused by the brake booster delay, during transitions from regen to friction braking. As an example, the case where the regen is ramped out at a low speed threshold, and the hydraulic braking ramped in, can be considered.
2013-04-08
Journal Article
2013-01-1473
Eric Rask, Danilo Santini, Henning Lohse-Busch
The recovery of braking energy through regenerative braking is a key enabler for the improved efficiency of Hybrid Electric Vehicles, Plug-in Hybrid Electric, and Battery Electric Vehicles (HEV, PHEV, BEV). However, this energy is often treated in a simplified fashion, frequently using an overall regeneration efficiency term, ξrg [1], which is then applied to the total available braking energy of a given drive-cycle. In addition to the ability to recapture braking energy typically lost during vehicle deceleration, hybrid and plug-in hybrid vehicles also allow for reduced or zero engine fueling during vehicle decelerations. While regenerative braking is often discussed as an enabler for improved fuel economy, reduced fueling is also an important component of a hybrid vehicle's ability to improve overall fuel economy.
2013-04-08
Technical Paper
2013-01-1463
Junzhi Zhang, Chen Lv, Xiaowei Yue, Mingzhe Qiu, Jinfang Gou, Chengkun He
As one of the key technologies of electrified vehicles, regenerative braking offers the capability of fuel saving by converting the kinetic energy of the moving vehicle into electric energy during deceleration. To coordinate the regenerative brake and friction brake, improving regeneration efficiency and guaranteeing brake performance and brake safety, development of special brake systems for electrified vehicles is needed. This paper presents a new type of electrically-controlled regenerative braking system (EABS) that has been developed for electrified passenger vehicles, which has the potential to be brought into production in China. By utilizing as much as possible mature components, integrating cooperative regeneration with ABS/TCS functions, EABS can achieve high regeneration efficiency and brake safety while providing system reliability, low development cost and development risk. This article describes the layout of the newly developed regenerative braking system.
2013-04-08
Technical Paper
2013-01-0412
Wenkai Xu, Hongyu Zheng, Zongyu Liu
Nowadays, the endurance mileage of electric vehicle is commonly short. For the purpose of enhancing the endurance mileage of 4WD electric vehicles, this paper proposes a new control strategy based on the generation efficiency of in-wheel motors. When the brake strength is low, the strategy defines the torque on which the motor has the highest generate efficiency as the upper limit of the braking torque of the front axle. What's more, the proportion of mechanical braking force is reduced. Because of these, the vehicle has a higher generation power. The simulation model is built up by using Matlab/Simulink and CarSim software, and the strategy is simulated under several driving cycles. The result shows that, comparing with the two traditional braking force distribution strategies, the new strategy can obviously improve the regenerative efficiency.
2013-03-25
Technical Paper
2013-01-0062
Sandro Boltshauser, Thomas Hibon, Roger Mateu
Driven by the will to gain further know-how and experience in the field of electric vehicles, and to demonstrate IDIADA's engineering capability, IDIADA decided to convert an existing light commercial vehicle, a Nissan Cabstar, into a fully electric vehicle. The brake department of Applus+ IDIADA investigated and developed different concepts of Regenerative Braking Systems (RBS) for this Electric Vehicle project, all of which based on the existing braking system, but with extended sensors. Thanks to their developments and technologies, Applus+ IDIADA succeeded in demonstrating the potential of electric vehicles. This presentation, with focus on the development and integration of the concept, aims at giving a brief overview on the results achieved so far.
2013-01-09
Technical Paper
2013-26-0155
Siddartha Khastgir, Prasad Warule
Regenerative braking has become one of the major features for a hybrid vehicle as it converts brake energy into electrical energy storable into battery and leads to an increase in overall fuel efficiency of the vehicle. Traditional regenerative braking systems are designed such that the mechanical braking force from the friction brakes is varied in order to get maximum electric braking. This is the optimum method; however, such a system calls from electronics (Anti-lock Braking System) for regulation of mechanical braking leading to an increased cost. In this paper, the authors present a new strategy for implementing a regenerative brake strategy without changing the mechanical brake system of a conventional vehicle converted to a hybrid vehicle. The electric motor that serves as the traction motor or the Integrated Starter Generator (ISG) system, is used for regenerative braking also. There is no change in the other vehicle specifications as compared to the conventional vehicle.
Viewing 1 to 30 of 171

Filter