The Experts below are selected from a list of 4614 Experts worldwide ranked by ideXlab platform
Hyunsoo Kim - One of the best experts on this subject based on the ideXlab platform.
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development of brake system and Regenerative Braking cooperative control algorithm for automatic transmission based hybrid electric vehicles
IEEE Transactions on Vehicular Technology, 2015Co-Authors: Jiweon Ko, Sungyeon Ko, Byoungsoo Yoo, Jae Seung Cheon, Hanho Son, Hyunsoo KimAbstract:In this paper, a brake system for an automatic transmission(AT)-based hybrid electric vehicle (HEV) is developed, and a Regenerative Braking cooperative control algorithm is proposed, with consideration of the characteristics of the brake system. The brake system does not require a pedal simulator or a fail-safe device, because a hydraulic brake is equipped on the rear wheels, and an electronic wedge brake (EWB) is equipped on the front wheels of the vehicle. Dynamic models of the HEV equipped with the brake system developed in this study are obtained, and a performance simulator is developed. Furthermore, a Regenerative Braking cooperative control algorithm, which can increase the Regenerative Braking energy recovery, is suggested by considering the characteristics of the proposed hydraulic brake system. A simulation and a vehicle test show that the brake system and the Regenerative Braking cooperative control algorithm satisfy the demanded Braking force by performing cooperative control between Regenerative Braking and friction Braking. The Regenerative Braking cooperative control algorithm can increase energy recovery of the Regenerative Braking by increasing the gradient of the demanded Braking force against the pedal stroke. The gradient of the demanded Braking force needs to be determined with consideration of the driver's Braking characteristics, Regenerative Braking energy, and the driving comfort.
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Cooperative Regenerative Braking control algorithm for an automatic-transmission-based hybrid electric vehicle during a downshift
Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2012Co-Authors: Chihoon Jo, Jiweon Ko, T Yeo, H Yeo, Sungho Hwang, Hyunsoo KimAbstract:A cooperative Regenerative Braking control algorithm is proposed for a six-speed automatic-transmission-based parallel hybrid electric vehicle (HEV) during a downshift that satisfies the requirements for Braking force and driving comfort. First, a downshift strategy during Braking is suggested by considering the re-acceleration performance. To maintain driving comfort, a cooperative Regenerative Braking control algorithm is developed that considers the response characteristics of the electrohydraulic brake. Using the electrohydraulic brake's hardware and an HEV simulator, a hardware-in-the-loop simulation (HILS) is performed. From the HILS results, it is found that the proposed cooperative Regenerative Braking control algorithm satisfies the demanded Braking force and driving comfort during the downshift with Regenerative Braking.
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Analysis of a Regenerative Braking system for Hybrid Electric Vehicles using an Electro-Mechanical Brake
International Journal of Automotive Technology, 2009Co-Authors: J. K. Ahn, H. B. Jin, K H Jung, Sungho Hwang, H S Kim, Dong-hyun Kim, Hyunsoo Kim, S. H. HwangAbstract:The Regenerative Braking system of the Hybrid Electric Vehicle (HEV) is a key technology that can improve fuel efficiency by 2050%, depending on motor size. In the Regenerative Braking system, the electronically controlled brake subsystem that directs the Braking forces into four wheels independently is indispensable. This technology is currently found in the Electronic Stability Program (ESP) and in Vehicle Dynamic Control (VDC). As Braking technologies progress toward brake-by-wire systems, the development of Electro-Mechanical Brake (EMB) systems will be very important in the improvement of both fuel consumption and vehicle safety. This paper investigates the modeling and simulation of EMB systems for HEVs. The HEV powertrain was modeled to include the internal combustion engine, electric motor, battery and transmission. The performance simulation for the Regenerative Braking system of the HEV was performed using MATLAB/Simulink. The control performance of the EMB system was evaluated via the simulation of the Regenerative Braking of the HEV during various driving conditions. [PUBLICATION ABSTRACT]
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Regenerative Braking algorithm for a hybrid electric vehicle with cvt ratio control
Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2006Co-Authors: H Yeo, Sungho Hwang, Hyunsoo KimAbstract:AbstractA Regenerative Braking algorithm is proposed for a hybrid electric vehicle with a continuously variable transmission (CVT) to make the maximum use of the Regenerative Braking energy. In the Regenerative Braking algorithm, the Regenerative torque is determined by considering the motor capacity, battery state of charge (SOC), and vehicle velocity. The Regenerative Braking force is calculated from the brake control unit by comparing the demanded brake torque and the motor torque available. The wheel pressure is reduced by the amount of the Regenerative Braking force and is supplied from the hydraulic brake module. In addition, the CVT speed ratio control algorithm is suggested during Braking for optimal motor operation. The optimal operation line is proposed to operate the motor in the most efficient region while keeping the motor speed as low as possible by considering engine noise and friction. It is found from the experiments that the Regenerative Braking algorithm with CVT ratio control offers an...
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vehicle stability control with Regenerative Braking and electronic brake force distribution for a four wheel drive hybrid electric vehicle
Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2006Co-Authors: D Kim, Hyunsoo KimAbstract:AbstractVehicle stability control for a four-wheel drive (4WD) hybrid electric vehicle is investigated using the Regenerative Braking of the rear motor and electrohydraulic brake (EHB). A fuzzy-rule-based control algorithm is proposed, which generates the direct yaw moment to compensate for the errors of the sideslip angle and yaw rate. Performance of the stability control logic is evaluated for J-turn and single-lane change. It is found from the simulation results that the Regenerative Braking of the rear motor is able to provide improved stability compared with the vehicle performance without any control. It is found that better performance can be achieved by applying the Regenerative Braking plus the EHB control. In addition, the optimal distribution ratio of the EHB force is presented to minimize the EHB power consumption. The simulation results show that the required torque level by the optimal EHB distribution ratio control is much lower than that of the fixed distribution ratio, while providing alm...
Jiweon Ko - One of the best experts on this subject based on the ideXlab platform.
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development of brake system and Regenerative Braking cooperative control algorithm for automatic transmission based hybrid electric vehicles
IEEE Transactions on Vehicular Technology, 2015Co-Authors: Jiweon Ko, Sungyeon Ko, Byoungsoo Yoo, Jae Seung Cheon, Hanho Son, Hyunsoo KimAbstract:In this paper, a brake system for an automatic transmission(AT)-based hybrid electric vehicle (HEV) is developed, and a Regenerative Braking cooperative control algorithm is proposed, with consideration of the characteristics of the brake system. The brake system does not require a pedal simulator or a fail-safe device, because a hydraulic brake is equipped on the rear wheels, and an electronic wedge brake (EWB) is equipped on the front wheels of the vehicle. Dynamic models of the HEV equipped with the brake system developed in this study are obtained, and a performance simulator is developed. Furthermore, a Regenerative Braking cooperative control algorithm, which can increase the Regenerative Braking energy recovery, is suggested by considering the characteristics of the proposed hydraulic brake system. A simulation and a vehicle test show that the brake system and the Regenerative Braking cooperative control algorithm satisfy the demanded Braking force by performing cooperative control between Regenerative Braking and friction Braking. The Regenerative Braking cooperative control algorithm can increase energy recovery of the Regenerative Braking by increasing the gradient of the demanded Braking force against the pedal stroke. The gradient of the demanded Braking force needs to be determined with consideration of the driver's Braking characteristics, Regenerative Braking energy, and the driving comfort.
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Cooperative Regenerative Braking control algorithm for an automatic-transmission-based hybrid electric vehicle during a downshift
Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2012Co-Authors: Chihoon Jo, Jiweon Ko, T Yeo, H Yeo, Sungho Hwang, Hyunsoo KimAbstract:A cooperative Regenerative Braking control algorithm is proposed for a six-speed automatic-transmission-based parallel hybrid electric vehicle (HEV) during a downshift that satisfies the requirements for Braking force and driving comfort. First, a downshift strategy during Braking is suggested by considering the re-acceleration performance. To maintain driving comfort, a cooperative Regenerative Braking control algorithm is developed that considers the response characteristics of the electrohydraulic brake. Using the electrohydraulic brake's hardware and an HEV simulator, a hardware-in-the-loop simulation (HILS) is performed. From the HILS results, it is found that the proposed cooperative Regenerative Braking control algorithm satisfies the demanded Braking force and driving comfort during the downshift with Regenerative Braking.
Xujian Li - One of the best experts on this subject based on the ideXlab platform.
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amt downshifting strategy design of hev during Regenerative Braking process for energy conservation
Applied Energy, 2016Co-Authors: Liang Li, Xiangyu Wang, Kai He, Rui Xiong, Xujian LiAbstract:For hybrid electric vehicles (HEVs), Regenerative Braking might be the most effective way of energy conservation. However, the Braking energy usually cannot be regenerated completely due to the limit of the motor maximum torque. When the Braking torque provided by electric motor (EM) cannot meet the driver’s Braking demand, the hydraulic brake system should provide extra Braking torque, which results in Braking energy loss. Therefore, it is meaningful adjusting EM work point to maximize the Regenerative energy by transmission downshifting. In this paper, an HEV equipped with an automated manual transmission (AMT) is chosen as the study platform. First, simplified dynamic models of HEV system are built. Then, the process and advantages of AMT downshifting are analyzed and the characteristics of Regenerative Braking are obtained with different gear positions and different, of which two kinds of downshifting strategy are proposed on basis. At last, hardware-in-loop tests are carried out, and results show that the energy conservation of Regenerative Braking process with downshifting can be increased by 10.5–32.4% compared to that without downshifting.
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Analysis of downshift's improvement to energy efficiency of an electric vehicle during Regenerative Braking
Applied Energy, 2016Co-Authors: Liang Li, Xiangyu Wang, Jian Song, Xujian Li, Kai He, Chenfeng LiAbstract:Downshift during Regenerative Braking helps to improve the energy efficiency of electric vehicles. Two main problems are involved in the downshift process. One is the determination of optimal downshift point, and the other is the cooperative control of Regenerative Braking and hydraulic Braking. In order to achieve a systemic solution to these problems, a hierarchical control strategy is brought forward for an electric vehicle with a two-speed automated mechanical transmission. For the upper controller, an off-line calculation and on-line look-up table method is adopted to obtain the optimal downshift point, and a series Regenerative Braking distribution strategy is designed. For the medium controller, a nonlinear sliding mode observer is designed to obtain the actual hydraulic brake torque. For the lower controller, cooperative control of Regenerative Braking and hydraulic Braking is given to ensure brake safety during downshift process, and a resembling pulse width modulation method is proposed to regulated the hydraulic brake torque. Simulation results and hardware-in-loop test show that the proposed algorithm is effective in improving the energy efficiency of electric vehicles.
Liang Li - One of the best experts on this subject based on the ideXlab platform.
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amt downshifting strategy design of hev during Regenerative Braking process for energy conservation
Applied Energy, 2016Co-Authors: Liang Li, Xiangyu Wang, Kai He, Rui Xiong, Xujian LiAbstract:For hybrid electric vehicles (HEVs), Regenerative Braking might be the most effective way of energy conservation. However, the Braking energy usually cannot be regenerated completely due to the limit of the motor maximum torque. When the Braking torque provided by electric motor (EM) cannot meet the driver’s Braking demand, the hydraulic brake system should provide extra Braking torque, which results in Braking energy loss. Therefore, it is meaningful adjusting EM work point to maximize the Regenerative energy by transmission downshifting. In this paper, an HEV equipped with an automated manual transmission (AMT) is chosen as the study platform. First, simplified dynamic models of HEV system are built. Then, the process and advantages of AMT downshifting are analyzed and the characteristics of Regenerative Braking are obtained with different gear positions and different, of which two kinds of downshifting strategy are proposed on basis. At last, hardware-in-loop tests are carried out, and results show that the energy conservation of Regenerative Braking process with downshifting can be increased by 10.5–32.4% compared to that without downshifting.
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Analysis of downshift's improvement to energy efficiency of an electric vehicle during Regenerative Braking
Applied Energy, 2016Co-Authors: Liang Li, Xiangyu Wang, Jian Song, Xujian Li, Kai He, Chenfeng LiAbstract:Downshift during Regenerative Braking helps to improve the energy efficiency of electric vehicles. Two main problems are involved in the downshift process. One is the determination of optimal downshift point, and the other is the cooperative control of Regenerative Braking and hydraulic Braking. In order to achieve a systemic solution to these problems, a hierarchical control strategy is brought forward for an electric vehicle with a two-speed automated mechanical transmission. For the upper controller, an off-line calculation and on-line look-up table method is adopted to obtain the optimal downshift point, and a series Regenerative Braking distribution strategy is designed. For the medium controller, a nonlinear sliding mode observer is designed to obtain the actual hydraulic brake torque. For the lower controller, cooperative control of Regenerative Braking and hydraulic Braking is given to ensure brake safety during downshift process, and a resembling pulse width modulation method is proposed to regulated the hydraulic brake torque. Simulation results and hardware-in-loop test show that the proposed algorithm is effective in improving the energy efficiency of electric vehicles.
Xiangyu Wang - One of the best experts on this subject based on the ideXlab platform.
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hierarchical control strategy with battery aging consideration for hybrid electric vehicle Regenerative Braking control
Energy, 2018Co-Authors: Xiangyu Wang, Cunan QinAbstract:Abstract Regenerative Braking is a key technology for hybrid electric vehicles (HEVs) to improve fuel economy, and it is a multi-objective control problem, which should ensure vehicle Braking safety, recover more energy, and protect components from aging. As is known, battery is the most sensitive component in hybrid powertrain, so a large recover current can cause damage to the battery and reduce its life. However, the damage to is usually ignored in Regenerative Braking. Therefore, this paper proposed a hierarchical control strategy with battery aging consideration to solve the problem. In the up-level controller, the control targets are to recover more energy and minimize aging of the battery in general Braking mode, and ensuring the vehicle Braking safety in emergency Braking mode at the same time. The low-level controller receives the commands of the up-level controller, and controls the pneumatic Braking system and the electric motor (EM). The constraints of maximum EM torque and maximum battery charging power are set to protect the EM and the battery. Simulation tests are designed to indicate the effects of Regenerative Braking on battery aging and the control effectiveness of the proposed method, and controller-in-the-loop tests are carried out to verify the real-time calculation performance.
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amt downshifting strategy design of hev during Regenerative Braking process for energy conservation
Applied Energy, 2016Co-Authors: Liang Li, Xiangyu Wang, Kai He, Rui Xiong, Xujian LiAbstract:For hybrid electric vehicles (HEVs), Regenerative Braking might be the most effective way of energy conservation. However, the Braking energy usually cannot be regenerated completely due to the limit of the motor maximum torque. When the Braking torque provided by electric motor (EM) cannot meet the driver’s Braking demand, the hydraulic brake system should provide extra Braking torque, which results in Braking energy loss. Therefore, it is meaningful adjusting EM work point to maximize the Regenerative energy by transmission downshifting. In this paper, an HEV equipped with an automated manual transmission (AMT) is chosen as the study platform. First, simplified dynamic models of HEV system are built. Then, the process and advantages of AMT downshifting are analyzed and the characteristics of Regenerative Braking are obtained with different gear positions and different, of which two kinds of downshifting strategy are proposed on basis. At last, hardware-in-loop tests are carried out, and results show that the energy conservation of Regenerative Braking process with downshifting can be increased by 10.5–32.4% compared to that without downshifting.
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Analysis of downshift's improvement to energy efficiency of an electric vehicle during Regenerative Braking
Applied Energy, 2016Co-Authors: Liang Li, Xiangyu Wang, Jian Song, Xujian Li, Kai He, Chenfeng LiAbstract:Downshift during Regenerative Braking helps to improve the energy efficiency of electric vehicles. Two main problems are involved in the downshift process. One is the determination of optimal downshift point, and the other is the cooperative control of Regenerative Braking and hydraulic Braking. In order to achieve a systemic solution to these problems, a hierarchical control strategy is brought forward for an electric vehicle with a two-speed automated mechanical transmission. For the upper controller, an off-line calculation and on-line look-up table method is adopted to obtain the optimal downshift point, and a series Regenerative Braking distribution strategy is designed. For the medium controller, a nonlinear sliding mode observer is designed to obtain the actual hydraulic brake torque. For the lower controller, cooperative control of Regenerative Braking and hydraulic Braking is given to ensure brake safety during downshift process, and a resembling pulse width modulation method is proposed to regulated the hydraulic brake torque. Simulation results and hardware-in-loop test show that the proposed algorithm is effective in improving the energy efficiency of electric vehicles.
