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SOC (State of charge) plays an important role in vehicle energy management, utilization of battery pack capacity, battery protection. Model based SOC estimation algorithm is widely regarded as an efficient computing method, but battery model accuracy and measuring noise variance will greatly affect the estimation result. This paper proposed an adaptive mixed estimation algorithm. In the algorithm, the recursive least squares algorithm was used to identify the battery parameters online with a second-order equivalent circuit model, and an adaptive unscented Kalman method was applied to estimate battery SOC. In order to verify the effect of the proposed algorithm, the experimental data of a lithium battery pack was applied to build a simulation model. The results show that the proposed joint algorithm has higher estimation accuracy and minimum root mean square error than other three algorithms.

Due to the rapid development of road infrastructure and vehicle population in China, the fuel consumption and emission of on-road vehicles tested in China World Transient Vehicle Cycle (C-WTVC) cannot indicate the real driving results. But the test results in China Heavy-duty Commercial Vehicle Test Cycle-Coach (CHTC-C) based on the road driving conditions in China are closer to the actual driving data. In this paper, the model for predicting the performance of heavy-duty vehicles is established and validated. The fuel consumption and NOx emission of a Euro VI heavy-duty coach under C-WTVC and CHTC-C tests are calculated by employing the developed model. Furthermore, the fuel consumption of the test coach is optimized and its sensitivity to the driving factors is analyzed.

As one of the core components of electric vehicles(EV), the drive motor system has a significant impact on the EV operation performance. The interior permanent magnet synchronous motor (IPMSM) has a wide range of applications in EV, due to its high efficiency, high power density, high torque current and wide speed range. In the field of EV, motor control system is required to have a high operating range. IPMSM operates at constant torque mode below rated speed and constant power mode above rated speed. The back electromotive force(Back-EMF) generated by the rotor in the constant power mode causes the inverter output voltage to saturate. Therefore, it is necessary to ensure that the controller is still operating in the linear region by applying a flux weakening(FW) current to the stator.

The thermophysical parameters and amount of composite phase change materials (PCMs) have decisive influence on the thermal control effects of thermal management systems (TMSs). At the same time, the various thermophysical parameters of the composite PCM are interrelated. For example, increasing the thermal conductivity is bound to mean a decrease in the latent heat of phase change, so a balance needs to be achieved between these parameters. In this paper, a prismatic LiFePO4 battery cell cooled by composite PCM is comprehensively analyzed by changing the phase change temperature, thermal conductivity and amount of composite PCM. The influence of the composite PCM parameters on the cooling and temperature homogenization effect of the TMS is analyzed. which can give useful guide to the preparation of composite PCMs and design of the heat transfer enhancement methods for TMSs.

To restrain the environmental and energy problems caused by oil consumption and improve fuel economy of heavy-duty commercial vehicles, China started developing relevant standards from 2008. This paper introduces the background and development of China's national standard “Fuel consumption test methods for heavy-duty commercial vehicles”, and mainly describes the test method schemes, driving cycle and weighting factors for calculating average fuel consumption of various vehicle categories. The standard applies to heavy-duty vehicles with the maximum design gross mass greater than 3500 kg, including semi-trailer tractors, common trucks, dump trucks, city buses and common buses. The standard adopts the C-WTVC driving cycle which is adjusted on the basis of the World Transient Vehicle Cycle[1, 2] and specifies weighting factors of urban, rural and motorway segments for different vehicle categories.

To determine the vehicle chassis requirements, wheel force transducer (WFT) have been the best option when it is being used in targeting customer correlation or determining the effective use of the proving ground. However, using wheel force transducer in customer correlation fleet test is often unfeasible due to the huge cost and low practicability. As a result, engineers have to choose other transducer measures. This paper describes an effective approach of wheel force prediction by using the frequency response function (FRF) model of vehicle dynamic system. A vehicle system linear modelling technique is used. For the system identification of FRF, the acceleration and wheel force time history data, as system input and output, are collected from an instrumented passenger car as it traverses in different real-world proving ground surfaces. The obtained FRF represents the complex suspension mechanical model. Once the FRF is calculated, the predicted force signal can be implemented.

This paper presents the feasibility study of using the worldwide harmonized light vehicles test cycle (WLTC) for the fuel consumption certification of Chinese Light-duty (LD) vehicles. First, the key steps and the technical routes of the development process of WLTC are summarized. Second, the operation data of 3082 vehicles in 41 typical cities of China are collected throughout the year. Then, the characteristics of the acquisition data are compared with WLTC. Finally, the feasibility of using WLTC for fuel consumption certification of Chinese LD vehicles is analyzed in three aspects, includes operation characteristics, weighting factors and fuel consumption. The result shows that there is obvious difference between WLTC and Chinese reality, and WLTC is not suitable for the fuel consumption certification of Chinese LD vehicles.

In this study, the effect of volatile fractions from engine lubricating oil on diesel particle emissions were studied experimentally. One commercial CF lubricating oil was used and distilled to subtract the different volatile fractions with boiling temperature of 220 °C, 260 °C and 300 °C, respectively. Oils derived from this distillation process were applied as the lubricating oil and following engine experiments were conducted. Diesel primary particles were sampled with a costume designed thermophoretic system. A fast response particulate spectrum equipment was employed to study the size distribution and number concentration of particles in the exhaust. Transmission electron microscopy was used to characterize the size distribution of the primary diesel particles relates to different oil volatile fractions.

This paper presents a novel powertrain control system specifically designed for longitudinal motion-control applications of an automated-manual-transmission vehicle, whereby the clutch and throttle modulation and gear change are highly coordinated such that the vehicle can precisely track the target acceleration or deceleration command even during an upshift or a downshift. An observer-free method for estimation of the engine’s operating point under various working condition is developed to compensate for limited sensing and enable effective feed-forward control of the engine torque and the clutch pressure. With minor modifications of the coordination strategies in the existing powertrain control system, the proposed control system can prevent stalling the engine from a standing start and achieve smoother shifting and faster dynamic response of the powertrain system, where non-smooth actuator nonlinearities are addressed explicitly, robustly, and efficiently.

With the continuous development of the electrical vehicles (EVs), the electric power network and transportation network are interconnected by EVs which require a coordinated operation of the two networks. In view of these coupled networks, this paper proposes a charging navigation strategy for EVs based on charging power adjustment, which can not only provide the navigation path with the shortest total operational time for EVs from the origin node to the completion of charging, but also effectively reduce load fluctuations in the electric power system. In the electric power system, an innovative optimization strategy for adjusting the EV charging power distribution is proposed, which can adjust the charging power in a timely and effective manner according to the response of EV charging. The multi-objective particle swarm optimization (MOPSO) algorithm and the improved Dijkstra algorithm are used for solving the obtained the EV charging power adjustment plan and charging paths.

The aim of the study was to investigate the difference between car-to-e-bikes and car-to-pedestrian accidents. The China In-depth Accident Study (CIDAS) database was searched from 2011 to 2013 for pedestrians and e-bikes struck by car, van and SUV fronts, which resulted in 104 pedestrian and 85 e-bike cases where information was sufficient for in-depth analysis. Reconstruction by PC-Crash was performed for all of the sampled cases. Pre-crash parameters were calculated by a MATLAB code. Focus was on prototypical accident scenarios and causes; speed as well as possible prevention countermeasures. It has been shown that traffic light violations, road priority violations, and unsure safety (these situations included misjudgments, unpreparedness, proximity to other road users, inappropriate speeds, etc.…) are the main causes in both the VRU groups. Distinctions were found for aspects of car collision speed, accident scenario, distribution of head contact points and so on.

The two-wheeler is a vehicle that runs on two wheels, which is classified as motorcycle, electric-bicycle, and bicycle in this research. China has the largest number of two-wheelers and relevant accidents in the world. The two-wheeler riders have a high level of vulnerability, creating a significant necessity to better understand the characteristics according to the road-user group. The objective of this paper is to study the characteristics and analyze the causes of two-wheeler accidents in China using the CIDAS (China In-Depth Accident Study) Database. 2012 cases of two-wheeler accidents with riders injured or dead were collected from the CIDAS Database from 5 cities (Changchun, Beijing, Weihai, Ningbo and Foshan) in China over a period of 5 years (2011.07-2016.06).

The automotive active infrared detection system is usually applied to the night driver assistance system or the diver attention monitoring system. However, the infrared light emitted by the active infrared detection system can cause damage to retina, cornea and eye crystals. This paper has studied the photobiological safety of the infrared light source used in the automotive active infrared detection system. Although it has been already have the general requirements of photobiological safety in international standards, there is not any requirements for automotive active infrared detection system. The range of the active infrared detection system depends on the radiation intensity of the infrared light source, but too much radiation intensity will cause harm to retina, cornea and eye lens when the infrared light source is too close to eyes.

A control strategy for searching the optimal working interval based on multi-parameter logic threshold is proposed for the power system of distributed hybrid electric vehicles. The battery state of charge working area and boundary velocity threshold are combined with the optimal engine working curve. Offline simulation of 0-32 km/h acceleration performance is conducted. To further verify the validity of generating C code, a hardware-in-the-loop (HIL) test platform based on MATLAB/RTW/xPC target is built. Real-time simulation and real-time performance comparison test are performed. Test results show that the designed multi-parameter logic threshold control strategy achieves reasonable allocation of energy and improves the dynamic performance of vehicles. The xPC HIL simulation test system is feasible and provides a fast test verification method for vehicle control strategy development.

OBD (On-Board Diagnostic) test system is applied to research influences of environmental parameters (altitude and environment temperature) on real-world NOx emission and fuel consumption for heavy-duty diesel trucks in this paper. The research results indicate that altitude and environment temperature have great influence on NOx emission rate and fuel consumption. High altitude in range of 3000~4000 m results in NOx emission rate is lower than low and moderate temperature because of air intake amount decreasing. However the fuel consumption rate is higher than lower altitude because altitude influences real-time changes of air inflow and combustion conditions in the cylinder of the engine. NOx emission rate and fuel consumption is more stable at different vehicle speed, VSP and RPM at high altitude, and NOx emission rate fluctuate dramatically at low and moderate altitude. The fuel consumption rate is higher at 10~20 °C than that at lower and higher temperature.

Most of the Advanced Driver Assistance System (ADAS) applications are aiming at improving both driving safety and comfort. Understanding human drivers' driving styles that make the systems more human-like or personalized for ADAS is the key to improve the system performance, in particular, the acceptance and adaption of ADAS to human drivers. The research presented in this paper focuses on the classification and identification for personalized driving styles. To motivate and reflect the information of different driving styles at the most extent, two sets, which consist of six kinds of stimuli with stochastic disturbance for the leading vehicles are created on a real-time Driver-In-the-Loop Intelligent Simulation Platform (DILISP) with PanoSim-RT®, dSPACE® and DEWETRON® and field test with both RT3000 family and RT-Range respectively.

Because of the advantages of excellent power, fuel economy and zero-emission characteristics, electric buses have been used widely as cities’ short-range commuter vehicles. However, the high-frequency noise becomes more prominent for the powertrain system of the electric bus due to the lack of noise masking effect for the traditional internal combustion engine. To improve the noise characteristic of electric bus powertrain, the identification of the main noise source of the powertrain is well needed. In this paper, the effects of the motor and transmission on the noise level of the electric bus powertrain have been studied using lead packaging method. The variations of acoustical power level of the powertrain according to different rotation speed and torque under the conditions of only motor covered and only transmission covered have been discussed.

T-BOX can manage the vehicle’s operation data and position data, and provide the following functions, positioning, vehicle status, motor data, BMS working status, charging status and status alarm, which may effectively promote the development of electric vehicle. Meanwhile, it may bring a series of problems, especially the electromagnetic compatibility (EMC) problems. In this paper, for the exceed standard limits problem of a particular T-BOX sample in radiation emission (RE) and conducted emissions(CE) test process, π filter is designed and added to the positive polar and negative polar of power supply based on the analysis of hardware circuit. The conduction emission test results of T-BOX after optimized can meet the requirements of GB/T 18655-2010 Vehicles, boats and internal combustion engines-Radio disturbance characteristics-Limits and methods of measurement for the protection of on-board receiver standard.

In this paper, it was researched the degradation characteristics of catalytic performance of three kinds of DPFs (C1, C2 and C3, with precious metal concentrations being 15, 25 and 35 g/ft3 respectively) after diesel truck aging. It is found out that the crystallinity of three kinds of DPF samples (Used) in full vehicle aging was higher than that of fresh samples (Fresh) and aged samples (Aged) in the laboratory. Compared with Fresh samples, the concentration of Pt atom in precious metal on the surface of Aged and Used samples tends to decrease in most cases. Activities to CO and C3H8 of Aged and Used samples of three kinds of DPFs had all been degraded, and activity degradation showed a substantial correlation with concentration reduction rate of precious metal on the carrier surface. NO2 productivity of Used samples all rose. Crystallinity of DPF samples after full vehicle aging in Inlet, Middle and Outlet areas successively increased.

The fatigue load spectrum of the physical proving ground is the necessary input for fatigue life analysis of vehicle parts and components. It is usually obtained by Road Load Data Acquisition (RLDA) and loads decomposition using multi-body dynamics tools. Virtual Proving Ground (VPG) methodology is gradually replacing this technical strategy. The belgian road is the typical event in durability test, in this paper, the flexible body and FTire model are applied to the vehicle multi-body dynamics model in order to improve the simulation accuracy. The result shows that all the wheel center force, shock absorber displacement and axial force acquired by VPG simulation have excellent correlation with real vehicle measured data. It is also proved that the virtual proving ground technology is a reliable and effective method to obtain the fatigue load spectrum in the early stage of development.