Home > Hot Topics > Car

Hot Topic

Car

Car

A comparative analysis of the policies for new energy industry in China and Japan: from the perspectives of policy tools and industrial ecosystem

LIU Zhaoguo;HAN Haochen

Contemporary Economy of Japan,Vol 37,No. 02

【Abstract】 Since the global financial crisis of 2008, most countries in the world have taken the new energy vehicle industry as an important industry to seize highlands in the future industrial competition. As a power in the automobile industry in the world, Japan has issued a series of strategies and plans in the new energy vehicle industry in recent years. Through the joint efforts of the central government and local governments, a scientific and effective new energy vehicle policy system has formed, which has promoted the infrastructure construction and business marketing for new energy vehicles. With regard to the new energy vehicle policy, China and Japan have some similarity when choosing policy tools. However, there are also a lot of differences between them. The aspects that the differences lie in can be concluded as follows: policy orientation, research and developmen framework, usage of policy tools like subsidies, and so on.

Spatial Driving Cycle for City Bus Considering Energy Management for Electric Vehicles

XIE Shao-bo;LIU Tong;CHEN Huan;WEI Lang

China Journal of Highway and Transport,Vol 31,No. 01

【Abstract】 To realize the optimal energy management for electric vehicles, the spatial driving cycle for the city bus was implemented including both the speed and road grade. With the sampled data in Xi’an city, the short trip including speed and information of road grade was extracted, and the spatial driving cycle was synthesized by the principal component analysis method and hierarchical clustering methodology. Meanwhile, the error between characteristic parameters of synthetic conditions and the source data was compared. Then the energy management strategy for a plug-in hybrid electric vehicle (PHEV) was simulated with the typical methods including the charge depletion and charge-sustaining (CD-CS) and dynamic programming (DP) based on 20 consecutive new running cycles, which reached approximately 100 km. Meanwhile, the influence of spatial and plane driving cycle and road grade on the energy management was analyzed and further compared. The results showed that the maximum and average errors of characteristic parameters were 9.44% and 4.63%, respectively. For CD-CS and DP strategies, the braking energy in the spatial driving cycle increased by 32.80% and 33.03%, respectively, compared with the braking energy in the plane cycle. The recovery energy obtained during the braking would increase with the increasing grade scalar. Besides, it is impossible for the DP strategy to realize the optimal energy distribution corresponding to the actual working conditions, without considering the braking power during the process of upslope and minus grade. The energy consumption cost for both strategies increased by 14.69% and 10.43% respectively in consideration of road grade. Moreover, the energy cost would increase dramatically with the increasing scalar of road grade, whilst in particular, the energy cost of the CD-CS method presented a more rapid growing rate than that of the DP method.

What Features Do Young Novice Drivers Want in Their Car?

Bridie Scott-Parker

Urban Transport of China,Vol 16,No. 03

【Abstract】 Young novice driver road safety remains an intractable problem; independently-licensed young drivers with access to their own vehicle at greatest risk on the road. Moreover, vehicle safety is a critical factor in the survivability of road crashes for all road users, including the vehicle occupants and vulnerable road users such as cyclists and pedestrians. To better understand vehicle choice, and therefore to gain insight into where young novice drivers weigh vehicle safety amid other considerations, teens from two Australian states were given the opportunity to design their ‘perfect car’. The findings have intervention implications for young novice driver injury prevention and safety promotion specifically, and for drivers of all ages and driving experience more generally. Teens rated features other than safety very highly in their ‘perfect car’, and it is likely these non-safety-focused features similarly rate highly in vehicle purchase decisions. Parents and teens alike need to be educated regarding risks associated with non-safety-focused features–and benefits associated with safety features–with consideration of insurance or other incentives for purchasing and driving safer vehicles. Such incentives and education should target drivers (and passengers) of all ages more generally. In addition, the methodology is also an innovative means by which to engage with intervention targets, revealing potential messaging avenues for a particularly vulnerable population.

Parameter Matching and Control Strategies of Hybrid Energy Storage System for Pure Electric Vehicle

HU Jian-jun;ZHENG Yong;HU Zhi-hua;XIAO Jun

China Journal of Highway and Transport,Vol 31,No. 03

【Abstract】 In order to solve problems of low power density, poor ability of heavy current charge and discharge and short cycle life of power battery used in the electric vehicle, a new hybrid energy storage system (HESS) composed of battery and ultracapacitor (UC) was taken as an object of research. The optimal approach of parameter matching for HESS was proposed under the typical cycle condition. Under the premise of satisfying the energy demand and power demand of HESS, the multiple objective optimization of the total cost and the total mass was carried out by taking the power battery capacity and the UC capacity as the optimization variables. On this basis, considering motor demand power and UC state of charge, the filtration-based rule control strategy was established to reduce output current of power battery. And the hybrid fuzzy control strategy was put forward to better adapt to different cycle conditions. The primary power distribution coefficient of power battery was obtained by the main fuzzy controller on the basis of the motor power demand, power battery state of charge and UC state of charge. Meanwhile, the modified power distribution coefficient of power battery was obtained by the sub-fuzzy controller based on the motor power demand and the difference between the current state of UC and the target value. To be specific, the optimal power coefficient of power battery was obtained by dint of two controllers. The vehicle power performance, economy, and power battery current and temperature characteristics were simulated and analyzed. The results show that, compared with the pure electric vehicle equipped with the conventional battery energy storage system, the proposed HESS with the two control strategies has the better performance. The acceleration time within 100 kilometers decreases by 6.89% and 9.85%, respectively, whilst the total energy consumption under NYCC condition decreases by 14.15% and 19.08%. The maximum battery output current under NYCC decreases by 63.4% and 65.17%, respectively, and power battery temperature rise decreases by 22.87% and 61.53%, respectively.

Disclaimer: Some of the images in this website are derived of the public network, whose copyrights still belong to the authors. If there exist any infringements, please contact us to delete them.
`