Applied Mechanics and Materials Vols. 291-294

Abstract: The liquefied natural gas (LNG) floating storage and regasification unit (FSRU) is a kind of LNG receiving terminal forms on the sea. Nowadays, it is the most widely used sea receiving terminal form in the engineering project as it has many advantages. In this paper, the characteristics of the FSRU were discussed based on comparing of the several LNG offshore receiving terminal. The application and trend of the FSRU in China was analyzed. It was found that FSRU is recommended for LNG import in East and South coast of China.

Abstract: A statistical analysis was conducted on the 182 gas accidents occurring 2006 to 2012 mainly from the two aspects of number of accidents and death toll of coal mines．By applying pie charts，bar charts，packing diagram and tendency charts，the rule of gas accidents was distinctly revealed．

Abstract: The need of electric vehicle charging stations is described in this paper, and in the paper, the electric vehicle users are classified into three categories, among which Type A users are of strong regular, type B users weak while type C users are randomness. On the basis of historical data, the tenure at a future time is easily to be predicted with the method of multiple linear regressions. Then according to the relevant national policies, the investigation and the Bass diffusion model, the proportion and charging power demand of all types of users can be predicted. Finally, based on the number of all types of users, the request of charging duration, the reserve capacity of routine maintenance, special events and other factors, a reasonable prediction of the conventional charging stations in the particular region is reasonably made. The result of the example shows that the method has strong practicality.

Abstract: With the developing of new energy technology, China’s new energy vehicle industry has been developing positively, but also accompanied with some problems. On the basic of the systematic analysis of new energy vehicle and its characteristics, and the situation of new energy vehicle industry in China, we deeply analyzed the existing problems of new energy vehicle industry. In the light of the government, research institute and enterprise, this paper proposed some improvement measures. Finally, in accordance with the policy in China, ten years goal of new energy vehicle industry was investigated. Aiming to provide some theoretical guidance for China’s new energy vehicle industry.

Abstract: This paper describe an approach to optimize the economy of electric vehicles’fast charging station investment with service satisfaction be constraints. An optimized model is proposed to study the relationship between the number of charge devices and economy of investment, which is based on the internal rate of return. Some service index like the queuing time and queuing length based on queuing theory are calculated to make sure the result reasonable and attainable for both investors and customers. At last, an example based on a conventional traffic flow and service intensity is simulated on Matlab to prove the effectiveness of the model.

Abstract: As an important infrastructure of electric vehicles (EVs), EV fast charging station is of great significance in the popularization and development of EVs. Through the analysis of the characteristics of EV’s arriving time and charging duration in fast charging station, the stochastic service system was introduced and the queuing system model based on queuing theory was established. By calculating the indexes of the queuing system model, the desire model was used to optimize the number of EV chargers, which could save customers’ waiting time and reduce the investment of charging station. Finally, an example was simulated and calculated with MATLAB used as a simulation tool to verify the effectiveness of this approach.

Abstract: Through the present situation research to the development of EV in China, analyzed of China's EV with a foreign related technology gap, EV development related facilities and EV marketing problems, combined with the development of our country market is actual, discussed EV technology innovation, EV infrastructure the construction and management and to improve the EV industry policy countermeasures.

Abstract: The charger for the electric vehicle (EV) is a nonlinear device, and will cause harmonic pollution when put into operation. This paper, firstly, analyzes harmonic caused by charger theoretically and defines its equivalent model as a three-phase full-bridge controlled rectifier, getting the characteristics of charger through the Fourier analysis of the switching function. Secondly, this paper builds the simulation model of the charger using Matlab/Simulink and replaces the car battery with a nonlinear resistor with resistance value changing over time. The parameters in the simulation model are the same as the charging stations in use and the results verify the charger’s harmonic characteristics. Finally, compared with the measured data, the results show the simulation model is suitable for engineering calculations.

Abstract: The purpose of this study is to propose a method to improve the total energy regenerated by two motors connected with Continuously Variable Transmission (CVT) in the power-train during reducing speed of automobiles, such as Electrical Vehicles (EVs) and Hybrid Electrical Vehicles (HEVs). In this study, to change the regenerating condition, initial speed-ratio of the CVT was changed to change the rotation speed of the SM during reducing speed of vehicle, since regenerated energy is affected by the rotational speed of motor. In experiments and simulations, the total regenerated energy was investigated when the speed of the vehicle was reduced from 40 to 0 km/h with -1.23m/s2 of negative acceleration, while the initial speed-ratio of the CVT was changed from 0.6 to 1.4. To investigate the effect of changing the initial speed-ratio of CVT on total regenerated energy, at first, the regenerated energy was measured by a test system driven by a single motor and a CVT. The total regenerated energy by two motors was also calculated by the simulation considering properties of constitutions in the power-train. Maximum improvement of total regenerated energy by one motor was obtained when initial speed-ratio of the CVT was approximately 0.9. It was confirmed that appropriate condition of the initial speed-ratio of the CVT was existed to improve regenerated energy. Total energy which was regenerated by two motors was improved approximately 122% in maximum by determining appropriate shift condition of the CVT, compared with that of conventional power-train driven by one motor. Even when the data of regenerated energy by two motors was compared with that through gears (ig=1.0), 35.4% of improvement was obtained at the condition where the maximum improvement was obtained by two. To improve totally regenerated energy, it was more effective to set the initial speed-ratio of the CVT on the pass of speed-ratio of the CVT when the electric power was generated by two motors, compared with that by single motor.

Abstract: The accurate electric vehicle charging load model shall be established to analyze potential challenges of static and dynamic stability brought by electric vehicles. In this paper, experiments with the electric vehicle charger and battery were carried out to analyze the model characteristics. And then this model was compared to the composite load model. At last, the modeling approach of static and dynamic model of electric vehicles was proposed.