الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Recently, the increasing concern over the environmental impact of the internal combustion engine vehicles (ICEVs), together with the soaring of oil prices, has led to a renewed interest in electric vehicles
(EVs). EV will be more and more popular in the development of the world in the next decades for many reasons like saving petrol, low pollution and high efficiency compared to ICEVs. EV uses electrical motors for propulsion, there are four major types of electrical motor drives used for EVs as follows: Brushed DC Motor (BDCM) drives, induction motor drives, Switched Reluctance Motor (SRM) drives and Brushless DC Motor (BLDCM) drives.
Recently, BLDCM is becoming increasingly popular because it replaces mechanical commutator used in BDCM with an electronic devices that
improves reliability in addition to many advantages -compared with BDCM- like high torque per weight, more efficient, reduced noise and maintenance-free operation. In addition to advantages in EV hub such
as: reduced hardware size and weight, simplified transmission mechanism and no reduction gear.
In order to design the BLDC motor for the application of the EV, it is
very important to decide the suitable scope of the BLDC motor parameters. It is corresponding to the given specifications of the EV propulsion, and accomplished by computing the dynamic equation coupled with the electrical equations. The method for sizing the motor and main control circuit components of the EVs is achieved.
Nowadays, electric actuators are more and more used for applications
requiring high reliability. In aeronautic, several actuators are used for the same function. Thus, when a fault occurs, the motor and the inverter are disconnected. This kind of redundancy is not acceptable in car industry because of required compactness and low cost. The system reliability should be taken into account especially at EV
applications. In a faulty case, the motor has to still operate even with
lower performance in order to park the car or reach home. To improve
the reliability of the system, the commonly admitted idea is to increase
the redundancy.
For cost limitations the number of switches has to be as lower as
possible. So, Eight Switches Bridge Converter (ESBC) was proposed to
achieve electrical separation between phases and increase reliability of
the system In order to verify the effectiveness of the proposed ESBC, at first simulation model is developed using MATLAB. Then, the complete
BLDCM drive incorporating the proposed eight switched bridge converter has been successfully implemented. The ESBC is carried out the electrical segregation between motor phases. This is achieved through four conditions of disconnecting phase for different switches.
The results are confirmed the feasibility and effectiveness of the
proposed converter.