Sharif Digital Repository

Determining the power ratio of the electric motor to the total power in parallel hybrid electric vehicles is of great importance that has a major impact on electric vehicle performance. The so-called Hybridization Factor is selected based on the desired performance indices of the vehicle. In practice, the effect of hybridization factor is observable on all the main indices of vehicle performance such as maximum speed, gradeability, pollutant emission, fuel consumption, etc. This ratio should be determined considering the desired performance indices and priorities. In this paper, the performance of an example electric vehicle is investigated through simulation results in ADVISOR software... 

A new optimal control law for direct yaw moment control, to improve the vehicle handling, is developed. Although, this can be considered as part of a multi-layer system, for the traction control of a motorized wheels electric vehicle, but the results of this study are quite general and can be applied to other types of vehicles. The dynamic model of the vehicle system is initially developed and, using the well-known optimal control theory, an optimal controller is designed. Two different versions of control laws are considered here and the performance of each version of the control law is compared with the other one. The numerical simulation of the vehicle handling with and without the use of... 

A new control law for direct yaw moment control of an electric vehicle is developed. Although this study is considered as part of a global control system for the traction control of a four motorized wheel electric vehicle, but the results of this study is quite general and can be applied to other types of vehicles. The dynamic model of the system has been analyzed and, in accordance with the optimal control theory, an optimal controller is designed. Two different versions of the control law have been considered and the performance of each version has been separately studied and compared with each other. Finally, the numerical simulation of the vehicle-handling model with and without the use... 

The reliability Studies are done in order to determine the probability of functioning or availability of different engineering systems. These studies can also provide a basis for comparing different structures of a system and can be used as a tool to improve the system design. Also, reliability is an important consideration in the planning, design and operation of transit system. Since the issue of the reliability of electric vehicles has not been sufficiently and seriously evaluated yet, so in this paper, the reliability of the various types of these kinds of vehicles will be discussed and then the reliability indices of them will be compared with each other and with the conventional cars  

Smart grids are envisioned to support large penetrations of electrical vehicles driven by economical and environmental signals. Nevertheless, distribution system operators are becoming concerned about distribution congestion that may occur in the network with multiple domestic plug-in hybrid electric vehicles (PHEVs) charging. Therefore, investigating the impacts of high PHEV penetration levels on the performance of distribution networks seems to be essential for system operators and planners. Doing so, in this paper, PHEV characteristics are precisely extracted from valid published reports and surveys. Accordingly, a comprehensive model for investigating the impacts of different PHEV... 

In this paper, a two-stage charging management framework is proposed to exploit the potential flexibility of Electric Vehicles (EVs). The aim is to reduce drastic variations in distribution system net load caused by integration of intermittent renewable distributed generation (DG) units. In the first stage, a home-based charging method is formulated in which the desired charging schedule of EVs is obtained by minimizing the cost of energy taking into account owners' preferences. The attained charging schedules are then announced to EVs Coordinator Agent (ECA) which, as the second stage, applies an LP optimization to reduce the cost of ramp provision. Moreover, an incentive scheme is... 

Societal concerns over global warming issues and dependence on fossil fuels have caused the vehicle market share of plug-in hybrid electric vehicles (PHEVs) to grow. A large penetration of PHEVs, however, would likely put higher stress on power systems. To lessen the PHEVs' harmful impacts on the distribution grid, this paper proposes a two-stage charging control strategy modeled on a renewable-based energy hub. In the first stage, a home-based charging control method is formulated in which the charging cost of PHEVs is considered as an objective. Running this procedure by PHEV schedulers in houses, in the second stage of the proposed strategy, the PHEV coordinator agent (PCA) applies a... 

Smart grids are envisioned to support large penetrations of electrical vehicles driven by economical and environmental signals. Nevertheless, distribution system operators are becoming concerned about distribution congestion that may occur in the network with multiple domestic plug-in hybrid electric vehicles (PHEVs) charging. Therefore, investigating the impacts of high PHEV penetration levels on the performance of distribution networks seems to be essential for system operators and planners. Doing so, in this paper, PHEV characteristics are precisely extracted from valid published reports and surveys. Accordingly, a comprehensive model for investigating the impacts of different PHEV... 

Plug-in Hybrid Electric Vehicles (PHEV) have the potential to limit emissions and reduce the cost of transportation. Although wide scale adoption of plug-in vehicles is still a few years away, politicians, electric utilities, and auto companies are eagerly awaiting the opportunities that may arise from reduction of emissions and gasoline and oil consumption, new services and increased revenues, and new markets that would create new jobs. For consumers, plug-in vehicles will significantly lower operational costs when compared with traditional gasoline cars. The savings are potentially high, in average, as electricity cost mile work out to about one forth of gasoline. But it is noticeable to... 

Despite the economic and environmental advantages of plug-in hybrid electric vehicles (PHEVs), the increased utilization of PHEVs brings up new concerns for power distribution system decision makers. Impacts of PHEVs on distribution networks, although have been proven to be noticeable, have not been thoroughly investigated for future years. In this paper, a comprehensive model is proposed to study the PHEV impacts on residential distribution systems. In so doing, PHEV fundamental characteristics, i.e., PHEV battery capacity, PHEV state of charge (SOC), and PHEV energy consumption in daily trips, are accurately modeled. As some of these effective characteristics depend on vehicle owner's... 

A massive focus has recently been made on demand response (DR) programs, aimed to the electricity price reduction, reliability improvement, and energy efficiency. Basically, DR programs are divided into twofold main categories, namely incentive-based programs and price- or time-based programs. The focus of this paper is on priced-based DR programs including consumer responses to the time differentiated pricing. Home load management (HLM) program is designed to control responsive appliances and charging/discharging cycles of plug-in hybrid electric vehicles (PHEVs) by the consumer. Uncertain parameters associated with PHEV, i.e. its departure/travelling time and energy consumption as well as... 

The electric assist control strategy is one of the well-known methods for managing the power sources of hybrid electric vehicles. Because of the dependence of the electric assist control strategy approach on its parameters, optimization of this strategy can improve its performance, which results in lower fuel consumption and lower emission levels. However, one of the main concerns about optimization of this strategy is its dependence on the driving behaviour. This paper aims to propose a new control strategy based on the electric assist control strategy with a smaller number of control parameters and less dependence on the driving behaviour. This strategy is usable only for vehicles equipped... 

Power management strategies play a key role in the design process of hybrid electric vehicles. Electric Assist Control Strategy (EACS) is one of the popular power management strategies for hybrid electric vehicles (HEVs). The present investigation proposes a new framework to advance the EACS. Dynamic Programming method is applied to an HEV model in several drive cycles, and as a result, some optimal operating regions are found. The obtained regions are almost distinct, and consequently, some threshold lines can be defined to separate them. The obtained threshold lines are used to eliminate some parameters of the EACS to reduce its sensitivity to the driving behavior. It is shown that by... 

The innovative powertrain configuration of modern electric vehicles with four-wheel independent drive (4WID) provides the possibility of simple and exact yaw moment control by controlling the electric motor of every wheel independently. In this study, a genuine control strategy for optimum direct yaw moment control is proposed. Although this can be considered as a global control system for traction control of 4WID electric vehicles, the analysis is quite general and can be applied to other types of vehicle. The directional vehicle model is derived and, in accordance with the optimal control theory, an optimum yaw moment controller is designed. Two versions of the control law are developed... 

To tackle the air pollution issues, Plug-in Hybrid Electric Vehicles (PHEVs) are proposed as an appropriate solution. Charging a large amount of PHEV batteries, if not controlled, would have negative impacts on the distribution system. The control process of charging of these vehicles can be centralized in parking lots that may provide a chance for better coordination than the individual charging in houses. In this paper, an optimization-based approach is proposed to determine the optimum PHEV parking capacities in candidate nodes of the distribution system. In so doing, a profile for charging and discharging of PHEVs is developed in order to flatten the network load profile. Then, this... 

Electric vehicles have been proposed as a proper replacement for fossil fuel-powered vehicles; however, due to the limited power density of electric vehicles batteries, these cars have been facing formidable challenges, such as limited traversed distance. In recent years, dynamic wireless chargers are introduced as an adequate way of addressing this problem in the hope that dealing with this issue can lead to an increase in the popularity of electric vehicles. In this paper, a design procedure for transmitter coil of a dynamic wireless electric vehicles charger is proposed. The procedure includes selecting the best possible shape and calculating optimum size of coils for proper operation of...