Papers by Keyword: Driving Cycle

Abstract: Design optimization of traction motors for light electric vehicles over an operating point is an adequate way of achieving higher overall efficiency under a standard driving scheme of the vehicle. However, this work proves that a direct comparison of similar candidates regarding efficiency values under a predetermined operating point does not yield sufficient information on the economy achieved on a specific driving pattern per candidate. This paper presents a comparative study on three similar surface mounted permanent magnet in-wheel motor configurations. On a first step, these configurations are compared in terms of efficiency and performance over one operating point. On a second step, efficiency maps of the designs under study are utilized to provide a wider picture of their efficiency attributes. On the final step, the three configurations are simulated driving a prototype light electric vehicle in the Urban part of the New European Driving Cycle and the results are discussed.

Abstract: Vehicles are the dominant source of many air pollutant emissions in urban areas. The effects caused by vehicle emissions have been receiving increasing attention, and recent epidemiological studies show elevated risks of cardiovascular morbidity, cancer, allergic diseases for drivers, commuters and individuals living near roadways. During the experimental research conducted in this paper, emission characteristics of Otto 1.1 EFI engine were investigated in varying operating modes in order to adequately simulate the movement of the Fiat Punto Classic (FPC) passenger car in city driving conditions in line with the New European Driving Cycle (NEDC). The NEDC is a stylized cycle, with periods of constant acceleration, deceleration and constant speed, and it is supposed to represent the typical usage of a passenger car in Europe. The analysis of exhaust gas samples was conducted by using the gas chromatography technique in combination with the photoionization detector (GC/PID). The results of emission tests indicate high concentration levels of toluene in the exhaust gas mixtures, ranging from 7.07 to 116.87 ppm. The total mass of the emitted toluene after 100 km of driving in accordance with the NEDC was 7.7647 g.

Abstract: The electrification of the powertrain is one of the best solutions in the quest for obtaining emissions within the even more narrow limits imposed by legislation, with no penalty to the dynamic performances of the vehicle. This article describes a study regarding the possibilities of hybridization of a road vehicle. Based on real life situations, the custom driving cycles have been defined by means of GPS tracking. These driving patterns were further used in a simulation environment to test various configurations of classical and hybrid powertrains. The performances of the vehicle before and after hybridization were compared pursuing the change in emissions and fuel consumption.

Abstract: Today, in the automotive emissions ultrafine and nanoparticles emissions are of very high importance because of their vulnerable effects to environment and human health causing respiratory problems like bronchitis, asthma, cardiovascular disease, and various types of cancers spreading in all age groups in the society leading to premature death [1]. Therefore, characterization of ultrafine and nanoparticles in terms of their size distribution and number concentration for the automobiles operating on various fuels and traffic conditions is of great importance in understanding the phenomenon and the adverse effects. Various research studies carried out at international level show the adverse health effects due to ultrafine particles from C.I. and S.I. engines and hence, there is definite need to examine for the particulate mass, size and number concentration considering social needs [2].Even after very stringent emission norms which were tightened over the years and today down to more than 97% from it’s baseline norms couldn’t show proportionate improvement in the ambient air quality. Climate effects inevitably lead to health effects leading to premature death due to ultrafine particles from the automotive exhaust [1]. Recent WHO report confirmed the vulnerable effect of diesel particles in terms of carcinogenicity and severe health effects of diesel fuel used in automotive sector [3]. European regulations has taken the steps to address this concern by introducing new norms for particle number and PM_2.5 as 6 x 10¹¹ and 4.5 mg/km respectively [4]. Investigations carried out on GDI vehicles show substantial ultrafine and nanosize particle emissions and by number, nearly all of the particles emitted by a diesel engine are nanoparticles which are also true for gasoline engines [5]. Like gasoline engines other S.I. engines, even though they look very clean as there is no visible smoke and large particles emitted in their exhaust, it is necessary to investigate them. Very limited research work has been carried out particularly, on CNG engines/ vehicles for their PM and PN levels at national and international level. Characterization of ultrafine and nanoparticles in terms of their size distribution and number concentration for the automobiles operating on various fuels and traffic conditions is of great importance in understanding the phenomenon and their significance.In this context and understanding the social need this research work was carried out to investigate experimentally the significance of CNG and diesel passenger car for it’s contribution to particle number (PN) and PM_2.5. This work includes comparative investigation of CNG and diesel passenger cars to characterize the ultrafine and nanoparticle emissions on modified Indian driving cycle. CNG passenger car show large peak of PN emissions during cold starting phase at the beginning of the test cycle which is almost twice that of diesel vehicle but it settles down to lower level as the vehicle gets warmed up. During acceleration and cruising operation on extra urban cycle under heavy load the PN emissions from CNG car are higher in magnitude. For diesel car, urban part of cycle contributes approximately 53% compared to 25% for CNG vehicle and rest 47% and 75% is contributed by extra urban part towards PN emissions.This research paper covers experimental Investigation carried out to compare the behavior of diesel and CNG passenger cars to characterize the particle emissions and to identify the significance of different operating phases viz. idling, acceleration, deceleration and cruising for their contributions to Particle number and size distribution pattern on urban and on extra urban part of the driving cycle.

Abstract: The typical fragment screening is one of the key links in the construction driving cycle. This problem is widely adopted Duration intercept method and clustering analysis method. Both methods are subjective,and the requirements for data of working conditions is huge. Aimed at these shortages, Using multivariate statistical theory discriminate analysis method, differentiate and classify the condition data. Basing on the statistical analysis of condition data, establish the discriminate function. With a city as example, Driving Cycle is established. Based on the discriminate analysis, classify the driving data. The effectiveness of the driving cycle is confirmed. The result of comparing discriminate analysis and traditional method shows that the driving cycle based on discriminate analysis can accurately reflect the characteristics of different kinds of driving conditions, and the data demand is reduced, meanwhile, the data acquisition test is simpler, the cost of establishing a driving cycle is cut, and development cycle is reduced.

Abstract: The article deals with the selection of optimal parameters of hybrid electric vehicle power sources. Construction of a hybrid electric vehicle with buffer energy storage based on double electric layer capacitors considers choosing minimal sufficient capacity of the storage.Required buffer storage capacity depends on the vehicle’s driving cycle. If it moves in cycle with the average power (the ratio of energy consumption to the duration of the cycle) higher than power of primary energy source, it means that missing energy would be drawn from the buffer storage and long-time moving in this cycle would discharge it. To avoid the case, the power of primary source and the capacity of buffer storage should be chosen in coordination.In the article the primary source power ensuring any driving cycle implementation with minimal storage capacity is calculated. It may be further reduced taking into account real driving cycles. A technique of selecting the combination of primary source power and buffer storage capacity based on numerical modeling of energy consuming process is proposed.

Abstract: Buffer energy storage capacity and primary energy source power are considered to define the performance of a hybrid electric vehicle. Required buffer storage capacity depends on the vehicle’s driving cycle. The margin of hybrid bus buffer energy storage is estimated on the base of trolleybus driving cycle recordings. The dependence of buffer energy storage on primary energy source power has been determined. Combinations of buffer energy storage and primary energy source power corresponding to different degrees of hybridization are discussed. The described analysis sequence can be applied for designing a hybrid powertrain and adjusting it to specific working conditions.

Abstract: A hybrid electric city bus was tested to explore its energy consumption and emissions under Chinese City Bus Cycle (CCBC) and World Transient Vehicle Cycle (WTVC). Energy consumption and emission factors under two cycles were compared. Contribution rates of different driving models to gaseous emissions were studied. Results showed, energy consumption and CO factor under CCBC were higher than those under WTVC, THC and NOx factors under CCBC were lower. Contribution rates of accelerating models to THC and NOx were 3~4 times higher than those of idle models, contribution rates of CO were more than ten times of that of idle models.

Abstract: Traction forces that vehicles use to propel their wheels depend on efficiencies of motors, power transmissions, and vehicle constructions. Behavior of driver on acceleration or deceleration varies responding to road conditions, traffic lights, and driving styles. Average speed estimation of the vehicle under known road conditions can be obtained from the standard driving cycles such as the urban driving cycle by NEDC and the highway fuel economy test cycle (HWFET) by EPA. An urban area, Khon Kaen province located in Northeastern part of Thailand, mostly has flat and rough road conditions that have not been well recorded. In this study a GPS device was installed on a midsize vehicle to record speed and time on roundtrip test drives. In this paper, the data on speed of the vehicle traveled from Department of Electrical Engineering, Khon Kaen University to four nearby locations were investigated than compared with standard driving cycles. These data offer greater knowledge and development in power consumption of electric vehicles and transportation sector.

Abstract: Using portable emission measurement system, an experimental study on the NOx emission characteristics of city bus in practical operation are conducted, the eigenvalue of driving cycle are analyzed by short trip method. The results show that: idling time accounted for 20.392%, ratio of acceleration which between -0.5 m/s2 and 0.5 m/s2 accounted for as high as 83.314%.NOx emissions are greatly affected by the speed of vehicle: the instantaneous rate and total amount of NOx emission under high speed are much higher than low speed, the average urea injection under high speed is 3.5 times than low speed. When the vehicle speed is between 20-25km/h, the average emission rate of NOx is about 0.074g/s，while the time proportion of urea injection is under 40%;while the vehicle speed is above 55km/h, the average emission rate of NOx is about 0.025g/s，while the time proportion of urea injection can reach as high as 80%.