ABSTRACT This work presents the synthesis of a motor with hysteresis motor torque-speed characteristic. The machine is synthesized from a conventional squirrel cage induction motor (SCIM) with high rotor resistance to leakage reactance ratio and a polyphase transfer field (TF) reluctance effect machine with an inverted torque-speed characteristics about the speed axis. Both motors are mechanically coupled and are connected in parallel to the supply. It is shown that the resultant torque which...
ABSTRACT On the 27th June, 1995, the Engineering professionals, policy makers , representatives from various sectors and the Hon. Minister of Works and Housing - Major General Abdukarim Adisa gathered here to witness the launching of the NIGERIAN ASSOCIATION OF ENGINEERING CRAFTSMEN (NAEC). An Association that into existence in 1993 after the amended Decree 55/70 by 27/92 which empowered COREN to regulate engineering profession in Nigeria.
ABSTRACT Isolated or Stand-alone power systems with the use of renewable energy sources have become cost-effective and a convenient option for areas where grid connection is neither available nor feasible. A hybrid combination of Renewable Energy Technologies (RETs) is considered to be the best suited alternative to an expensive grid extension for remote areas around the world. This research focuses on creating a model for electricity generation from a mix of renewable resources (hydro, sol...
Abstract Radio spectrum access is important for terrestrial wireless networks, commercial earth observations and terrestrial radio astronomy observations. The services offered by terrestrial wireless networks, commercial earth observations and terrestrial radio astronomy observations have evolved due to technological advances. They are expected to meet increasing users’ demands which will require more spectrum. The increasing demand for high throughput by users necessitates allocating addit...
ABSTRACT This work focused on Evaluating the Performance of the Unified Power Flow Controller (UPFC) on Fault Current Limitation in the Nigerian 330kV Power Network. The SIMULINK model of the Nigerian 330kV system was developed. The model of the UPFC was developed and integrated into the power system model. The proportional integral (PI) control parameters of the UPFC was optimized using genetic algorithm. Results from simulation carried out showed the versatility of the UPFC in the protecti...
Abstract The electric vehicle relies on electric motors for propulsion. In this report, the case was made for the induction motor as a suitable candidate for this tractive application. Being able to control the electric motor invariably implies efficient control of the vehicle. This work reports the six-step operation of the constant volts/hertz (V/f) control technique for voltage fed induction motor drives. Mathematical equations supporting the principle is discussed and the drive is modell...
ABSTRACT This work proposes a switching technique for cascaded H-Bridge (CHB) cells. A single carrier Sinusoidal PWM (SCSPWM) scheme is employed in the generation of the gating signals. A sequential switching and base PWM circulation schemes are presented for this fundamental cascaded multilevel inverter topology. With these proposed concepts, it is now possible to generate equal average switching signal patterns in all the constituting power semiconductor switches. This results in equal swi...
ABSTRACT The dynamic simulation is one of the key steps in the validation of the design process of the motor drive systems and it is needed for eliminating inadvertent design mistakes and the resulting error in the prototype construction and testing. A quality mathematical model of induction machine based on the dynamic equations and D-Q transformation technique is presented in rotor reference frame and a computer simulation of a 7.5kW three phase induction motor was carried out based�...
ABSTRACT Short circuit modelling and parameter extraction of a synchronous generator entails development of a mathematical model of three phase short circuit of a turbo generator and the study of its characteristics or envelops at short circuit under constant speed and saturated conditions.. The transient parameters have a significant impact on the magnitude of the fault currents generated within the machine during an event such as a 3 phase short-circuit. Power system designers routinely use...
Version:0.9 StartHTML:0000000105 EndHTML:0000007189 StartFragment:0000000141 EndFragment:0000007149 Short circuit modelling and parameter extraction of a synchronous generator entails development of a mathematical model of three phase short circuit of a turbo generator and the study of its characteristics or envelops at short circuit under constant speed and saturated conditions.. The transient parameters have a significant impact on the magnitude of the fault currents generated within th...
Abstract Automatic Three Phase Changer is considered one the most important element in the power distribution system as it works to reduce the problem during faulty condition time and also protecting high voltage to the consumption voltage. To achieve maximum efficiency of this phase faulty the stability of power consumption on the distribution center has a main role. This thesis aims to design, simulate and develop automated three phase changer by running different place. The system works a...