Comparing Fuel Consumption and Emission Levels of Hybrid Powertrain Configurations and a Conventional Powertrain in Varied Drive Cycles and Degree of Hybridization

Abstract

Hybrid electric powertrains in automotive applications aim to improve emissions and fuel economy with respect to conventional internal combustion engine vehicles. Variety of design scenarios need to be addressed in designing a hybrid electric vehicle to achieve desired design objectives such as fuel consumption and exhaust gas emissions. The work in this paper presents an analysis of the design objectives for an automobile powertrain with respect to different design scenarios, i. e. target drive cycle and degree of hybridization. Toward these ends, four powertrain configuration models (i. e. internal combustion engine, series, parallel and complex hybrid powertrain configurations) of a small vehicle (motorized three wheeler) are developed using Model Advisor software and simulated with varied drive cycles and degrees of hybridization. Firstly, the impact of vehicle power control strategy and operational characteristics of the different powertrain configurations are investigated with respect to exhaust gas emissions and fuel consumption. Secondly, the drive cycles are scaled according to kinetic intensity and the relationship between fuel consumption and drive cycles is assessed. Thirdly, three fuel consumption models are developed so that fuel consumption values for a real-world drive cycle may be predicted in regard to each powertrain configuration. The results show that when compared with a conventional powertrain fuel consumption is lower in hybrid vehicles. This work led to the surprisingly result showing higher CO emission levels with hybrid vehicles. Furthermore, fuel consumption of all four powertrains showed a strong correlation with kinetic intensity values of selected drive cycles. It was found that with varied drive cycles the average fuel advantage for each was: series 23 %, parallel 21 %, and complex hybrids 33 %, compared to an IC engine powertrain. The study reveals that performance of hybrid configurations vary significantly with drive cycle and degree of hybridization. The paper also suggests future areas of study.

Power Management Strategy of a Parallel Hybrid Three-Wheeler for Fuel and Emission Reduction

“…As mentioned before, powertrain design follows a sequential design approach, component sizing and design of power management strategy is carried out successively [29]. Powertrain component sizes are found from previous work [14]. Basic parameters of the hybrid powertrain components and the vehicle are summarized in Table 1.…”

“…Table 5 summarizes fuel and emission level change with the proposed rule-based control strategy compared to the DP results. To gauge the performance of the control strategy developed in real-life cycles, results are simulated in "Malabe" cycle from [14]. The "Malabe" real-life cycle is shown in Figure 21.…”

“…Table 5 summarizes fuel and emission level change with the proposed rule-based control strategy compared to the DP results. The ADVISOR parallel hybrid three-wheeler model and conventional powertrain model (internal combustion engine (ICE) based) developed in [14] are simulated over "Malabe" cycle with the same parameters of the present study and fuel consumption results of the DP and proposed rule-based strategy are compared. Findings show that compared to the conventional (ICE-based) powertrain, fuel consumption of the parallel hybrid power train reduced 37.4% with ADIVISOR unoptimized strategy, 52.9% with the proposed optimized rule-base strategy and 57.0% with the DP.…”

“…Use of plug-in technology for parallel hybrid electric three-wheelers is studied by Padmanaban et al [13]. Comparative analysis of hybrid configurations of three-wheelers is carried out by a recent study from Maddumage et al [14]. The study examines the effect of hybrid configuration on fuel and emissions by studying conventional, parallel, series and complex powertrain designs for hybrid electric three-wheelers.…”

“…In addition, a sequential design methodology [29] (sizing and control is solved separately in a sequential manner) is used in developing the hybrid powertrain. The power management strategy is developed in the present study for the sized parallel hybrid powertrain from [14].…”