No abstract

BLDC motors are characterized by electronic commutation, which is performed by using an electric three-phase inverter. The direct control system of the BLDC motor consists of double loops; including the inner-loop for current regulating and outer-loop for speed control. The operation of the current controller requires feedback of motor currents; the conventional current controller uses two current sensors on the ac side of the inverter to measure the currents of two phases, while the third current would be accordingly calculated. These two sensors should have the same characteristics, to achieve balanced current measurements. It should be noted that the sensitivity of these sensors changes with time. In the case of one sensor fails, both of them must be replaced. To overcome this problem, it is preferable to use one sensor instead of two. The proposed control system is based on a deadbeat predictive controller, which is used to regulate the DC current of the BLDC motor. Such a controller can be considered as digital controller mode, which has fast response, high precision and can be easily implemented with microprocessor. The proposed control system has been simulated using Matlab software, and the system is tested at a different operating condition such as low speed and high speed.

The basic design of induction motors has not changed in the last years, with latest and good insulation materials, pre-simulation for design, computer optimization techniques in design and using automated manufacturing devices have resulted in motors of less cost per kW, heating reduction and smaller physical size. Due to standards by International of physical dimensions and frame sizes the motors from most manufacturers are physically interchangeable and they have similar performance characteristics, dimensions and electrical distribution of multiphase coils are affecting on magnetic field density, because of difficulty in measuring magnetic flux in each point of the machine computer simulations help in machine design to demonstrate and adjustments in magnetic flux distribution. Three-phase and six-phase induction motor electromagnetic models are developed in two-dimensions in the finite element method based software-tool Computer Solutions (COMSOL) Multiphysics. Frequency domain simulation result obtained magnetic field density comparison between three phase and six phase induction motors.

Software Defined Radio (SDR) has the flexibility to modify the characteristics of the receiving and transmitting radio device, without physically adjusting the hardware, due to development in the system. Because of the increasing need for wireless communication applications so as to enable consumers to communicate anywhere through information led to the emergence of many communication devices to include the large amount of applications that every one of the devices needs power and thereby increase the total power. This study confirms that the wireless communication system for secured transmit data, fast and inexpensive; can be done by implementing using Partial Reconfiguration (PR) modern technology in FPGA developing based on SDR. The Speed and performance can be improved. The area also can be decreased. The new Xilinx, Vertex Series FPGA, provides the provision of PR. The power consumption can be reduced by applying power reduction techniques in the blocks. The combination of MATLAB (Simulink and M-file) and Simulink HDL Coder offers flexible capabilities for analysis, design; simulation, implementation, and verification. With all these capabilities, in a single system to reduce the time spent tuning for reducing the algorithms and models during rapid prototyping and experimentation and less time on HDL coding. Contribution/ Originality: This study contributes in the existing literature review for implementing MC-CDMA wireless communication system using Partial Reconfiguration (PR) that is a new technology in FPGA. 1. INTRODUCTION The wireless communications revolution started with the mobile phone at the beginning of the 80's and all the improvements which have led to the multiplication of mobile and wireless communications networks and standards [1]. The 1st Generation (1G) of technology was characterized by analog means voice only; 1G quality was too low and also had connections to low speed, but they effectively offered the inherent easiness of mobile communications. The system used in 1G was Frequency Division Multiple Access (FDMA) [2]. The 2nd Generation (2G) of technology is digital in the United States, most of the devices and services were digital. The spread of digital mobile

In electrical vehicle applications, power density plays a significant role in improving machine performance. The main objective of this paper is to design and analyze the performance of in-wheel outer rotor permanent magnet synchronous motor (PMSM) used in electric vehicles based on a previously designed model. The key challenge is to achieve the best machine performance regarding the highest torque density and lowest torque ripple. This work also aims at reducing the machine cost by using permanent magnet (PM) material, which has less energy density than the PM used in the previously designed model. An optimization procedure is carried out to improve the generated torque, keeping the same aspects of size and volume of the selected machine. On the other hand, the other specifications of the machine are taken into consideration and are maintained within the acceptable level. According to their major impact on the machine’s performance, the most important parameters of machine designing is selected during the optimization procedure. This proposed machine is implemented and tested using the finite element software package “MagNet 7.4.1” with Visual Basic 16.0 programming language and MATLAB 9.5 Simulink for post-processing.