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In ISO 26262, the functional safety validation test of E / E system is required. Fault injection is a general method of functional safety validation test. AEBS is an important part of vehicle active safety, so it is very meaningful to study the fault injection test of AEBS. In this paper, a method of functional safety validation test of AEBS based on fault injection is studied, including the preparation, execution and passing standards of the test. This test method can be used to evaluate the effectiveness of the security mechanism and is suitable for functional security validation test.

In this paper, it was studied on effects of CDPF (catalyzed diesel particulate filters, (DPF) on the unregulated emissions, volatile organic compounds (VOCs), particulate carbon components, particulate polycyclic aromatic hydrocarbons (PAHs) and its toxicity from the diesel bus emissions. The results show that the VOCs were reduced by 57.6% by the CDPF, the total carbon (TC) were reduced by 70.4%. The PAHs from diesel bus were reduced up to 91.1% and the CDPF showed higher reduction rate for low-ring PAHs, such as 3-ring and 4-ring PAHs, while it presented lower selective for higher ring PAHs. The CDPF can obviously reduce the toxicity equivalent of different benzene ring PAHs, and there was no obvious effect on toxicity equivalent ratio of different benzene rings of PAHs 柴油公交车加装CDPF的非常规污染物排放特征分析 *

In this paper, the OBD (On-Board Diagnostic) method is used to study the effect of environmental parameters (altitude, ambient temperature) on the actual road NOx emissions and fuel consumption of heavy-duty diesel vehicles. The research results show that the effect of altitude on NOx emissions and fuel consumption is mainly attributed to changes of real-time air intake and combustion in the cylinder. Higher altitude results in increase in fuel consumption, but it is beneficial to reduce NOx emissions. From 10°C to 20°C ambient temperature, the fuel consumption rate is the highest but the NOx emission rate is the lowest. The ambient temperature from 20°C to 35°C creates the conditions for the generation of NOx so causes deterioration of NOx emission, and the oxygen enriched environment is created from -10°C to 10°C so increase production of NOx. The trend of the NOx emission rate and the fuel consumption rate are opposite at different altitudes and ambient temperatures, compared with the fuel consumption rate, the NOx emission rate is more sensitive to the vehicle speed, VSP and rotation speed.

To test and evaluate performance, fuel efficiency and emission of fuel cell hybrid vehicles, a laboratory equipped with a heavy duty chassis dynamometer is constructed by CATARC collaborates with Tsinghua University. The framework of the chassis dynamometer laboratory is designed. Then, three hydrogen consumption measurement methods are researched, and a hydrogen energy consumption measurement system for the laboratory is developed. Finally, the application of the chassis dynamometer laboratory is presented, especially several tests for the accuracy and the reliability of the hydrogen energy consumption measurement system is carried out. Certification tests and researches for both heavy duty and light duty fuel cell hybrid vehicles can be carried out in this chassis dynamometer laboratory.

Comparison of running resistance generated from on-road coasting tests and recommended calculation was analyzed in this paper. Using coefficient and multipoint setting methods, chassis dynamometer tests of Hybrid Electric Bus (HEB) were carried out to simulate on-road running resistance according to coasting test data. Test results show that the average relative error between coasting test results and computational resistance is larger than 9%, so road coasting test can not be replaced by any other calculating methods. The maximum relative error between coasting test resistance and simulated results is less than 3%.

Chassis dynamometer based test procedures were developed to benchmark the emissions and fuel economy performance of heavy duty hybrid electric vehicles (HEVs). And a hybrid electric bus (HEB) was tested according to the presented procedures to make a validation and get a picture of the HEB performance on the fuel economy, cold and hot start running emissions. Results show that the presented procedure is practical for heavy duty HEVs evaluation, and exhibited satisfying reproducibility.

Two different types of heavy-duty hybrid vehicles had been tested by portable emission measure system (PEMS). Analyzed the two hybrid vehiclespsila emission characteristics under different modes by cycle classification method and provided technical support to hybrid vehiclepsilas control strategy. The results showed that the two hybrid vehiclespsila tracking correlation coefficient (R2) were both more than 0.99. Series vehiclepsilas HC, CO and PM emissions factor were lower than parallel, but NOx and CO2 emissions factor were opposite. Series vehicle has the least exhaust emission mass under acceleration mode.