Ouyang M.,Tsinghua University |
Zhang W.,Higer Bus Company Ltd |
Wang E.,Tsinghua University |
Yang F.,Tsinghua University |
And 4 more authors.
Applied Energy | Year: 2015
Energy conservation is a very important task for the automotive industry. The use of hybrid electric vehicles can improve energy efficiency, thus reducing fuel consumption and carbon emissions. In this research, the performance characteristics of a novel coaxial power-split hybrid powertrain for a transit bus are presented. The power sources are a combination of a compressed natural gas (CNG) engine and supercapacitors. A mathematical model for the coaxial power-split hybrid powertrain is established. Subsequently, an analysis program is developed based on Matlab and Advisor. The parameters are specified using experimental data. Afterwards, a rule-based control strategy is designed and optimized from the viewpoint of energy efficiency. Later, the system performance is evaluated using the Chinese Transit Bus City Driving Cycle and compared to a conventional powertrain. The results indicate that the proposed coaxial power-split hybrid powertrain can fulfill the requirements of the transit bus and enhance the energy efficiency dramatically. Moreover, the average energy efficiency of the supercapacitors was found to be above 97% over the entire driving cycle. Using supercapacitors as energy storage devices for the coaxial power-split hybrid powertrain can effectively recover the kinetic energy during regenerative braking and is a good solution for transit buses that require frequent acceleration and deceleration. © 2015 Elsevier Ltd.
Chen S.-A.,Jiangsu University |
Chen S.-A.,Higer Bus Company Ltd |
Qiu F.,Higer Bus Company Ltd |
He R.,Jiangsu University |
And 2 more authors.
Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of Technology | Year: 2010
To improve pavement irregularity stability of high speed bus, working principle of this pavement irregularity disturbance steering movement and its influencing factors are researched. Firstly, dynamics model of bus's disturbance steering from pavement irregularity is established and corresponding state equation is obtained. Secondly, single factor influence analyses and dynamic variable parameter simulations of this steering movement in view of main influencing factors including static load on the front axle, tire cornering stiffness, coulomb damping in steering system and self-aligning torque from front wheel alignment are carried out. It is got that reducing coulomb damping in steering system and increasing static load on the front axle and self-aligning torque from front wheel alignment are feasible measures to decrease maximum lateral displace in the front of high speed bus. Finally, Vehicle tests are carried out to validate simulation results of maximal lateral displace on bus foreside under measures taken before and after, and test investigation shows that simulation predictions agree with test results. So some theoretic references can be obtained to improve pavement irregularity stability of high speed bus.
Shen F.-L.,Chang'an University |
Deng J.-T.,Higer Bus Company Ltd |
Xie X.-L.,Chang'an University |
Sun Z.-H.,Chang'an University
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport | Year: 2010
Aimed at 6120 coach, based on simulation software UG, ANSYS/LS-DYNA and finite element analysis (FEA) theory, the finite element model of coach body structure was established. According to the structure features of coach body, study of frontal crash FEA simulation was carried out at the initial speed of 50 km·h-1, the frontal crash deformation characteristics of its body structure were got. Aimed at the problem that the driving zone and driver living space were compressed seriously, some improvements of the front structure and the chassis were made in design. Simulation results show that the deformation speed of the driving zone decreases, as well as maximum values of the acceleration of the coach mass center and driver's seat measuring points decrease. The FEA simulation method has some reference and application value for coach body structure safety design of frontal crash and the relevant further study.