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A fuzzy logic technique is presented in this paper for sensorless speed and position identification of vector-controlled PWM inverterfed PMSM drives used in EV/HEV propulsion systems. Fuzzy logic is used to estimate the rotor speed and position. Operation of the drive is studied by numerical simulation. The performance for different drive conditions is also analyzed and the results are shown in the paper. Simulation results show that the proposed control method can be effectively used in controlling the PMSM drives with high performance for EV/HEV applications. It is found that the fuzzy logic system is reliable without using any speed or position sensor.

There is a clear trend towards Hybrid Electric Vehicles (HEV) due to the environmental concerns. On the other hand, with increasing hotel and ancillary loads and replacement of more engine driven mechanical and hydraulic loads with electrical loads, automotive systems are becoming more electric. This is the concept of More Electric Cars (MEC) which necessitates going to a higher voltage such as 42V for conventional cars. Can the evaluation of the 42V MEC smoothly lead to the Hybrid Electric Vehicles (HEV) and More Electric Hybrid Vehicles (MEHV)? In this paper, we investigate the feasibility of 42V & 14+42V electrical power systems for MEHV. Technical issues of such a solution are explored in detail.

The need of upfront modeling, simulation and design optimization has been ever increasing during full vehicle product development process. The overall vehicle system and component subsystem performances remain critical considerations for making final product release decision. With these challenges in mind, the work of this paper discusses the development of feasible CAE methods, tools, and processes for multi-objective design optimization. A full integrated tractor trailer truck vehicle is used as an example to demonstrate this capability. The proposed approach allows several design objectives to be simultaneously optimized, which might otherwise be extremely difficult to achieve with experimental methods.

Military and civilian vehicles are moving towards more electrification, in response to the increasing demand for multi-mode missions, fuel consumption and emissions reduction, and dual use electrical and electronic components. Consequently, the vehicle electric load is increasing rapidly. For military vehicles, these electrical loads include: the loads for electric traction (EV and HEV), cabin climate conditioning, vehicle control and actuation, actuation by wire (X by wire), sensors, reconnaissance, communications, weapons etc. All these requirements need to be supported by an efficient, fast responding and high capacity energy storage system. The electric load of a vehicle can be decomposed into two components--- static and dynamic loads. The static component is slowly varying power with limited magnitude, whereas the dynamic load is fast varying power with large magnitude. The energy storage system, accordingly, comprises of two basic elements.

Short circuit incidents on traction motors can cause ‘wheel-locking’ on the vehicle, and may have an adverse impact on vehicle stability. This paper investigates the necessity of fault-tolerant motors for EV and HEV traction applications. Reaction of resulting fault torques differ along with electric motor types and fault variety. The paper analyzes the short-circuit behavior of three basic motor types: permanent magnet, induction and switched reluctance motor. The analysis is based on the transient simulation of the three most common inverter short-circuit cases and their effect on vehicle stability.

The objective of this study is to optimize the injector power drive system for improved fuel injection quantity and timing control. The power drive system was optimized for improved injection repeatability under different operating conditions such as fuel supply pressures. A coupled simulation of injector electromagnetic, pintle (needle) rigid body motion and computational fluid dynamics (CFD) model was employed to generate the optimal values of the 1st stage current, the 1st stage on-time and the 2nd stage current. The simulation results were validated against the experimental data measured with a photo detector measurement system.

The recent growing interest in electric vehicle (EV) and hybrid electric vehicle (HEV) demands for an efficient, reliable and economical motor drive for electric propulsion. However, searching for a suitable traction motor becomes quite involved when vehicle dynamics and system architecture are considered. This paper makes an in-depth investigation on two highly important traction motor characteristics, extended speed range-ability and energy efficiency, from vehicular system perspective. The influences of these two motor drive features on a pure EV, a post-transmission, and two pre-transmission parallel HEV with 20% and 50% hybridization are studied in this paper. Two EV-HEV software packages ‘V-ELPH’ developed by Texas A&M University and ‘ADVISOR’ from NREL are used for simulation purposes. Based on the results in this paper, a systematic method is developed regarding the selection of traction drives for EV and HEV propulsion systems.

A vehicle's performance depends greatly on the operating conditions, such as journey type, driving behavior etc. Driving patterns vary with geographical location and traffic conditions. In today's global economy where automobile industries are concerned with both local and international markets, it becomes necessary to investigate vehicle performance for driving cycles of different countries and develop vehicle designs which are appropriate to the consumer's market. This paper concentrates on the issues related to designing hybrid electric vehicles. A method of optimizing the size of the principal hardware components of hybrid vehicles such as, electric motors, internal combustion engines, transmissions and energy storage devices based on the demands of different drive cycles is discussed in the paper.

It is important for engineering firms to be able to develop forecasts of recommended courses of action based on available information. In particular, engineering firms must be able to assess the benefit of performing information-gathering actions. For example, an automobile manufacturer may use a computer simulation of a hydraulic motor and pump in the design of a new vehicle. The model may contain random variables that can be more accurately determined through expensive information-gathering actions, e.g., physical experiments, surveys, etc. To decide whether to perform these information-gathering actions, the automobile manufacturer must be able to quantify the expected value to the firm of conducting them. However, the cost of computing the expected value of information (through optimization, Monte Carlo sampling, etc.) grows exponentially with the amount of information that is to be gathered and can often exceed the cost of actually gathering the information.

A Dual Power Split Electronic Continuously Variable Transmission (DPS-ECVT) with an input-split, output coupled, split-power-path configuration is proposed for improving overall system efficiency and range for electric vehicles. By modulating the power split ratio between the mechanical (planetary gear meshes) and electrical (Motor Generator Units) driveline components, a continuous range of gear ratios operating at higher efficiency is obtained. The proposed concept leverages two power-split units that lead to significantly reduced power flow through the electrical drivelines (compared with single speed EV transmissions as well as single power-split E-CVTs) while providing the same overall ratio spread for transmission operation.

A concept of “driving situation awareness”-driven energy management system for parallel hybrid electric vehicles (HEVs) is introduced. The essential feature of the proposed energy management system is to assess the driving environment (in terms of facility type combined with traffic congestion level) using long and short term statistical features of the drive cycle. Subsequently, this knowledge is provided to a system that makes intelligent decisions with respect to the torque distribution and charge sustenance tasks. Simulation work was carried out for the validation of proposed system, and the results reveal its viability for energy management of parallel hybrid vehicles.

Two parallel HEV control concepts: ‘thermostat’ and ‘power split’ are compared in this paper. To achieve a substantial improvement in fuel economy, the ‘thermostat’ or ‘on/off’ control technique intended to improve the fuel efficiency of a series HEV has been adopted and designed for parallel HEV. Among different ‘power split’ concepts developed for parallel hybrids only the ‘electrically assist’ algorithm is considered in this paper. These two control concepts are compared for three parallel HEV architectures: pre-transmission, post-transmission and continuous variable transmission hybrids. The comparison study also includes the effect of hybridization factor-the ratio of the electric power to the total propulsion power. The matrices of comparison are level of performance, energy consumption and exhaust emissions. The SAE J1711 partial charge test procedure is followed.

An electromechanical gear is presented along with design examples utilizing the electromechanical gear in hybrid electric vehicle drive trains. The designs feature the electromechanical gear (the Transmotor) in place of traditional mechanical transmissions and/or gearing mechanisms. The transmotor is an electric motor suspended by its shafts, in which both the stator and the rotor are allowed to rotate freely. The motor thus can provide positive or negative rotational energy to its shafts by either consuming or generating electrical energy. A design example is included in which the transmotor is installed on the output shaft of an internal combustion engine. In this arrangement the transmotor can either increase or decrease shaft speed by applying or generating electrical power, allowing the ICE to operate with a constant speed.