Advanced Materials Research Vols. 512-515

Abstract: Based on the vehicle dynamic model and it’s parameters, the drive train arrangement is chosen composed of power batteries, an electric motor and transmission, and the components’ performance parameters are determined according to the design requirement of performance indexes. The model of the electric vehicle is built, and the simulation and analysis of vehicle performance indexes, such as the ability to accelerate, top speed, climbing performance and the driving range, are conducted. The simulation results show that the performance index of the electric vehicle can fully meet the design requirement.

Abstract: The non-stationary characteristics of starting motor’s current can effectively reflect the faults of vehicle’s electrical starting system. Taking the working current of starting motor as original signal, the signal’s singular points were detected by wavelet transforming. And through comparing the singularity characteristics with normal state, the common faults of starting system were identified accurately. The practical application to a certain type of hybrid electric vehicle shows that the proposed method based on wavelet singularity analysis can effectively extract the key characteristics of starting current signal and realize the identification of electric starting system’s common faults.

Abstract: Methanol is an attractive alternative transportation fuel because it is a renewable resource and it is oxygenated, thereby providing the potential to reduce particulate emissions in gasoline engines. In this paper the key impacts to the properties of methanol blended with gasoline fuel are discussed. The property impacts including increased alcohol and oxygen content, stability, hygroscopicity, volatility and materials compatibility. The effect of the changed properties on engine performance, durability and emissions is also considered.

Abstract: Battery Electric vehicle (BEV) has been set as one of the most prominent sectors of automobile industry in China in the future due to its significant contribution to energy safety, low carbon emission and leading technology status in vehicle driven by new energy. High penetration of BEV will have obvious impacts on power systems, and its load characteristics are quite different from those traditional loads. Therefore with an eye on the safe, stable and economic operation of power system, this paper studied the impacts of EV on power systems from four aspects: total electricity demand, power rush in short period, power quality and vehicle to grid (V2G) technology. Total electricity demand by BEV charging in 2020 in China was firstly estimated in the paper, and it is sure that power system has the capability to meet this demand. However uncontrolled massive BEV charging will probably results in higher peak load and upgrading requirement of power systems, so orderly charging is required. EV battery is charged through rectifier, which will decrease power quality by harmonic current, therefore power electronic equipment is required to ensure power quality. Finally possibility of scheme of vehicle to grid (V2G) application is discussed when the scale of BEV is large enough and performance of EV battery is greatly improved.

Abstract: The use of CAN bus network on electric vehicles is of great significance, it can not only greatly reduce the costs of electric vehicles, but also increase the driving distance of electric vehicles. The stability of CAN bus load rate and CAN network communication rate plays a vital role to the CAN network，by studying and making use of SAEJ1939, this paper develops a vehicle network topology, then through calculating the bit rate of transfer time to calculate the load rate, combined with using the software named CANoe from the Vector company in Germany to analyse and simulate the sending cycle of each CAN bus node on pure electric vehicles. In this way,this paper analyses the reasonableness of CAN network design of the vehicle body. Finally this paper applies the on-site verification to prove the reliability of simulation results. This study is based on SAEJ1939 agreement CAN2.0B, did not make a study for CAN2.0A, so there are limitations, the findings may not apply to CAN2.0A.

Abstract: Handling dynamic model is established for the four-wheel independent steering electric vehicle (4WISEV) that has been developed by our research group. Handling dynamics simulation is conducted under Matlab environment with the parameters of the vehicle model, including the yaw rate, the lateral acceleration and the vehicle sideslip angle time domain and frequency domain characteristic simulation. Through analyzing the simulation results, it is indicated that, by adopting the feedforward control of the front steer angle and the feedback control of the yaw rate and vehicle speed which enable the vehicle sideslip angle to approximate zero, 4WISEV can effectively increase the handling stability of the vehicle and the tracking ability during steering process.

Abstract: In this paper, we investigate an underwater vehicle with two rudders suitable for working in Kuroshio near the eastern Taiwan, where the flow field of ocean current is less than 1.0m/sec. Lift and drag forces of the underwater vehicle submerged in the sea were calculated at different attack of angles and rudders by using finite element method. An on-site experiment with a prototype vehicle was also conducted located on Hsinta Fishing Harbor. Results show that lift force for the rudder of prototype vehicle near the sea surface is only 60% of theoretical calculations. To reduce the turbulence effect, the position of rudders in the front and the rear for the underwater vehicle should not be at the same level. Drag forces increase tremendously with increasing attack of angles compared with the effect of rudder’s quantity. The power-free underwater vehicle has been built and controlled steadily at 0.6~0.7m/sec flow velocity, suitable for carrying generators in Kuroshio.

Abstract: μC/OS-II is one of RTOS which has remarkable advantages, such as high reliability, high real-time ability, and easy code scalability. This paper transplanted it into BMS on electric vehicle successfully which was based on MC9S12XDP512 MCU hardware platform. Using quantitative comparison under specific tests, this paper also verified the real-time and reliability advantages of μC/OS-II.

Abstract: The main contributions of this paper are the development of forward-facing model of a series hydraulic hybrid vehicle (SHHV) power-train for medium size trucks, of which the fundamental architecture is described, together with dynamic equations and basic features of subsystem modules. A thermostatic SoC supervisory power management control algorithm is assessed, with the expectation that series configuration would maximize the fuel economy as engine is decoupled from the wheels. Simulation results over the urban driving cycle represent a significant departure from the conventional wisdom of operating the engine near its sweet spot and indicate what is preferred from the system stand-point, and also demonstrate the potential of the selected hybrid system to substantially improve vehicle fuel economy.

Abstract: Based on CFD technique，this paper discusses the applicability of different turbulence models and mesh partition method which are used to predict the hydrodynamic performance of AUV. Firstly, the hydrodynamic performance prediction method was gotten and was validated, and three different shapes autonomous underwater vehicles were designed. The hydrodynamic performances of the three autonomous underwater vehicles were predicted. Then, the advantage and disadvantage of the four autonomous underwater vehicles were obtained by comparing the resistance and pressure distribution. Based on these, two other AUV hulls were designed which combined the advantages of them, and the hydrodynamic performance was predicted. The calculation results showed that the resistance and hull pressure distribution were improved remarkably comparing with the parent model. The resistance coefficient of optimized hull is reduced by 20% compared to the parent hull.