Сравнение расхода топлива и уровня выбросов при обычной и гибридных конфигурациях трансмиссий c учетом циклов движения и степени гибридизации

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

Development Of Hydraulic Regenerative Braking Testbench

Hybrid vehicle is a vehicle that operates with the combination of two power sources. The hybrid technology helps reduces the vehicle fuel consumption and gas emissions through the regenerative braking and acceleration assist system. As most of the light duty vehicles are equipped with electric hybrid system, this project focuses on the implementation of hydraulic hybrid system into the light passenger vehicle to study the performance of hydraulic hybrid vehicle (HHV). The test bench for hydraulic hybrid system in parallel-through-the-road architecture is developed which involved the processes of hydraulic configurations selection, designing the control system, the hydraulic circuit layout and test bench CAD model, and analyzing the expected performance of regenerative braking system. The performance analysis comprises of V-belt drive selections for regenerative braking and validation of HHV deceleration rate using drive cycle data. The V-belt selections analysis shows that one V-belt type D can undergo regenerative braking without slip. For deceleration rate analysis, the average deceleration rate of HHV is much higher than that from drive cycle with the difference by 85% while the maximum deceleration rate of HHV have the difference by only 22% from the drive cycle value. Therefore, the modification on the control system is necessary to control the HHV deceleration. With the result of these analyses, the modification and complete fabrication of HHV test bench can be accomplished in future as well as the testing of hydraulic hybrid operation

An investigation into hybrid power trains for vehicles with regenerative braking

Imperial Users onl

Performance Analysis of Hybrid and Full Electrical Vehicles Equipped with Continuously Variable Transmissions

The main aim of this paper is to study the potential impacts in hybrid and full electrical vehicles performance by utilising continuously variable transmissions. This is achieved by two stages. First, for Electrical Vehicles (EVs), modelling and analysing the powertrain of a generic electric vehicle is developed using Matlab/Simulink-QSS Toolkit, with and without a transmission system of varying levels of complexity. Predicted results are compared for a typical electrical vehicle in three cases: without a gearbox, with a Continuously Variable Transmission (CVT), and with a conventional stepped gearbox. Second, for Hybrid Electrical Vehicles (HEVs), a twin epicyclic power split transmission model is used. Computer programmes for the analysis of epicyclic transmission based on a matrix method are developed and used. Two vehicle models are built-up; namely: traditional ICE vehicle, and HEV with a twin epicyclic gearbox. Predictions for both stages are made over the New European Driving Cycle (NEDC).The simulations show that the twin epicyclic offers substantial improvements of reduction in energy consumption in HEVs. The results also show that it is possible to improve overall performance and energy consumption levels using a continuously variable ratio gearbox in EVs

A Study on the Integration of a High-Speed Flywheel as an Energy Storage Device in Hybrid Vehicles

The last couple of decades have seen the rise of the hybrid electric vehicle as a compromise between the outstanding specific energy of petrol fuels and its low-cost technology, and the zero tail-gate emissions of the electric vehicle. Despite this, considerable reductions in cost and further increases in fuel economy are needed for their widespread adoption. An alternative low-cost energy storage technology for vehicles is the high-speed flywheel. The flywheel has important limitations that exclude it from being used as a primary energy source for vehicles, but its power characteristics and low-cost materials make it a powerful complement to a vehicle's primary propulsion system. This thesis presents an analysis on the integration of a high-speed flywheel for use as a secondary energy storage device in hybrid vehicles. Unlike other energy storage technologies, the energy content of the flywheel has a direct impact on the velocity of transmission. This presents an important challenge, as it means that the flywheel must be able to rotate at a speed independent of the vehicle's velocity and therefore it must be coupled via a variable speed transmission. This thesis presents some practical ways in which to accomplish this in conventional road vehicles, namely with the use of a variator, a planetary gear set or with the use of a power-split continuously variable transmission. Fundamental analyses on the kinematic behaviour of these transmissions particularly as they pertain to flywheel powertrains are presented. Computer simulations were carried out to compare the performance of various transmissions, and the models developed are presented as well. Finally the thesis also contains an investigation on the driving and road conditions that have the most beneficial effect on hybrid vehicle performance, with a particular emphasis on the effect that the road topography has on fuel economy and the significance of this

Urban and extra-urban hybrid vehicles: a technological review

Pollution derived from transportation systems is a worldwide, timelier issue than ever. The abatement actions of harmful substances in the air are on the agenda and they are necessary today to safeguard our welfare and that of the planet. Environmental pollution in large cities is approximately 20% due to the transportation system. In addition, private traffic contributes greatly to city pollution. Further, “vehicle operating life” is most often exceeded and vehicle emissions do not comply with European antipollution standards. It becomes mandatory to find a solution that respects the environment and, realize an appropriate transportation service to the customers. New technologies related to hybrid –electric engines are making great strides in reducing emissions, and the funds allocated by public authorities should be addressed. In addition, the use (implementation) of new technologies is also convenient from an economic point of view. In fact, by implementing the use of hybrid vehicles, fuel consumption can be reduced. The different hybrid configurations presented refer to such a series architecture, developed by the researchers and Research and Development groups. Regarding energy flows, different strategy logic or vehicle management units have been illustrated. Various configurations and vehicles were studied by simulating different driving cycles, both European approval and homologation and customer ones (typically municipal and university). The simulations have provided guidance on the optimal proposed configuration and information on the component to be used

An investigation on the effect of driver style and driving events on energy demand of a PHEV

Environmental concerns, security of fuel supply and CO2 regulations are driving innovation in the automotive industry towards electric and hybrid electric vehicles. The fuel economy and emission performance of hybrid electric vehicles (HEVs) strongly depends on the energy management system (EMS). Prior knowledge of driving information could be used to enhance the performance of a HEV. However, how the necessary information can be obtained to use in EMS optimisation still remains a challenge. In this paper the effect of driver style and driving events like city and highway driving on plug in hybrid electric vehicle (PHEV) energy demand is studied. Using real world driving data from three drivers of very different driver style, a simulation has been exercised for a given route having city and highway driving. Driver style and driving events both affect vehicle energy demand. In both driving events considered, vehicle energy demand is different due to driver styles. The major part of city driving is reactive driving influenced by external factors and driver leading to variation in vehicle speed and hence energy demand. In free highway driving, the driver choice of cruise speed is the only factor affecting vehicle energy demand

Сравнение расхода топлива и уровня выбросов при обычной и гибридных конфигурациях трансмиссий c учетом циклов движения и степени гибридизации

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.Применение гибридных электрических трансмиссий в автомобильной промышленности – это решение проблемы выбросов и экономии топлива в сравнении с обычными автомобилями с двигателем внутреннего сгорания. Для достижения желаемых результатов при проектировании гибридного электромобиля необходимо рассматривать различные варианты, учитывая при этом расход топлива и выбросы выхлопных газов. В статье представлен анализ проектирования автомобильной трансмиссии, рассмотрены различные варианты и ситуации, например, целевой цикл движения и степень гибридизации. Pазработаны четыре модели конфигурации трансмиссии (двигатель внутреннего сгорания, серийная, параллельная и комплексная конфигурации гибридной трансмиссии) для небольшого транспортного средства (моторизованный трехколесный автомобиль) с использованием программного обеспечения Model Advisor. Перечисленные конфигурации трансмиссии моделировались с различными циклами движения и разной степенью гибридизации. Во-первых, влияние стратегии управления мощностью транспортного средства и эксплуатационных характеристик всевозможных конфигураций трансмиссии исследуется на основе анализа выбросов выхлопных газов и расходов топлива. Во-вторых, циклы движения масштабируются в соответствии с кинетической интенсивностью и оценивается взаимосвязь между расходом топлива и циклами движения. В-третьих, разработаны три модели расхода топлива, так что расход топлива для реального цикла движения может быть спрогнозирован в отношении каждой конфигурации трансмиссии. Исследования показали, что по сравнению с обычной трансмиссией потребление топлива меньше у гибридных транспортных средств. Испытания дали неожиданный результат: более высокие уровни выбросов CO у гибридных транспортных средств. Кроме того, расход топлива всех четырех трансмиссий указывает на сильную корреляцию со значениями кинетической интенсивности выбранных циклов движения. Выявлено, что при различных циклах вождения в среднем предпочтение по топливу для каждого цикла составило: 23 % – для последовательных, 21 % – для параллельных и 33 % – для комплексных гибридов в сравнении с трансмиссией двигателя внутреннего сгорания. Эксперименты показали, что производительность гибридных конфигураций варьируется в зависимости от цикла вождения и степени гибридизации. В статье определены перспективные направления исследований

Energy Management System For Three-Wheel Light Electric Vehicle Using Multi-Sources Energy Models

Hybrid electric vehicles, plug-in hybrid electric vehicles, battery electric vehicles, fuel-cell vehicles are just a few technologies that are being researched worldwide today. Applying renewable energy such as battery, fuel cell and super-capacitor in the electric vehicle is a smart and ideal solution. However, battery as a single-source in electric vehicle has many disadvantages such as limited travel distance and longer charging time. Besides, battery reduces its electrical characteristics through high current flow, high temperature, self-discharge and low battery capacity level. Fuel cell has low power response during sudden energy demand and requires an expensive infrastructure for refueling. In case of light fuel cell vehicle, small tank is practical for exchange tank. In super-capacitor side, it cannot support enough energy for a single powered electric vehicle purposes, however can be used as secondary power supply. Thus, an intelligent energy management system (EMS) of various sources is necessary to counterbalance the drawback of the sources. To solve the problem, the objective of the research is to develop an intelligent EMS which can conduct multi-sources for three wheel light electric vehicle (LEV). A rule-based control algorithm which contains eight states in EMS is designed to control power switches and to ensure sufficient energy is delivered to the load. The work of this research begins by electrical analysis in PSPICE simulation which focuses in circuit design and testing the state condition. A close loop vehicle system implemented with intelligent EMS is designed in MATLAB/Simulink. The simulation model is simulated with a real three wheel scooter specification which has capacity of 5.4 kW DC machine. To show effectiveness of the developed vehicle system, the performance and efficiency of the vehicle simulation is compared with standard drive cycle such as ECE-47 and ECE-15. To justify the simulation model, a scaled-down lab test bench model is designed using dSPACE DS 1104. The LEV model with 18 W load power is implemented in the developed test bench prototype. As a result, the vehicle system specification for the lab test bench model is reduced accordingly to the ratio of load power. The power specifications of the multi-source models such as 30 W for fuel cell, 3 Ah for rechargeable sealed lead acid battery and 100F for super-capacitors have been used. An EMS hardware is designed to offer a bridge between MATLAB/Simulink and dSPACE DS 1104. In the EMS hardware design, the switching relay is used for selection of the sources and current transducers which are used for measuring load current and battery capacity. All input and output signals from the EMS hardware design are connected to the dSPACE DS 1104 for data presentation in graphical user interface. For the uphill simulation test, using ECE-47 drive cycle, multi-source energy models shows that the power effectiveness is 94.6% where as for the battery, as a single-source, it is 84.9%. The lab test bench model also proved that in extension of 33% of speed ECE-47 drive cycle, the energy efficiency of multi-source LEV is 80.2% which is better performance than that of combustion engine energy efficiency of 29.2%. Therefore, the system equipped with an intelligent control algorithm has promising potential in vehicle energy management applications for the future

Multi-objective optimisation for battery electric vehicle powertrain topologies

Electric vehicles are becoming more popular in the market. To be competitive, manufacturers need to produce vehicles with a low energy consumption, a good range and an acceptable driving performance. These are dependent on the choice of components and the topology in which they are used. In a conventional gasoline vehicle, the powertrain topology is constrained to a few well-understood layouts; these typically consist of a single engine driving one axle or both axles through a multi-ratio gearbox. With electric vehicles, there is more flexibility, and the design space is relatively unexplored. In this paper, we evaluate several different topologies as follows: a traditional topology using a single electric motor driving a single axle with a fixed gear ratio; a topology using separate motors for the front axle and the rear axle, each with its own fixed gear ratio; a topology using in-wheel motors on a single axle; a four-wheel-drive topology using in-wheel motors on both axes. Multi-objective optimisation techniques are used to find the optimal component sizing for a given requirement set and to investigate the trade-offs between the energy consumption, the powertrain cost and the acceleration performance. The paper concludes with a discussion of the relative merits of the different topologies and their applicability to real-world passenger cars