Nik Fasdi Nik Ismail

Fuzzy logic controller on DC/DC boost converter

This paper describes the design of a fuzzy logic controller using voltage output as feedback for significantly improving the dynamic performance of boost dc-dc converter by using MATLAB@Simulink software. The objective of this proposed methodology is to develop fuzzy logic controller on control boost dc-dc converter using MATLAB@Simulink software. The fuzzy logic controller has been implemented to the system by developing fuzzy logic control algorithm. The design and calculation of the components especially for the inductor has been done to ensure the converter operates in continuous conduction mode. The evaluation of the output has been carried out and compared by software simulation using MATLAB software between the open loop and closed loop circuit. The simulation results are shown that voltage output is able to be control in steady state condition for boost dc-dc converter by using this methodology.

Transient stability analysis on Sarawak's Grid using Power System Simulator for Engineering (PSS/E)

Transient stability analysis has become one of the major analyses in the power system to ensure the system stability to withstand a major disturbance. The effect of transient occurrence can lead to malfunction of electronic control equipment. Transient analysis can be conducted using simulation software package. One of the commercial simulation software package that used by industry worldwide is Siemens Power System Simulation for Engineering (PSS/E). This research paper highlights the usage of PSS/E to analyze Sarawaks Grid System stability using the simplest dynamic model that has been embedded into the program. To observe transient analysis using PSS/E, basic machine model such as generator, exciter and governor were used by varying default data in the program to find the best simulation output. This paper also analyzed the theory of critical clearing time (CCT) of fault occurrence between a transmission line near to the generator and far from the generator. CCT appears to be lesser when the fault occurs at a transmission line near to the generator. On the contrary, when fault occurs far from the generator, the duration of CCT is greater. The stability of the system is observed based on the machine rotor angle, machine speed, output electrical power and terminal voltage.

Comparative study of Fuzzy Logic controller and Proportional Integral Derivative controller on DC-DC Buck Converter

The main objective of this document is to compare the performance between Fuzzy Logic controller (FLC) and Proportional Integral Derivative controller (PIDC) in improving the performance of DC/DC Buck Converters. The evaluation of the output has been carried out and compared by software simulation using MATLAB Simulink. Fuzzy logic controller has been implemented to the system by developing fuzzy logic control algorithm. The signals will be processed based on the fuzzy logic rules-based and PID algorithm.

A comparative study of Proportional Integral Derivative controller and Fuzzy Logic controller on DC/DC Buck-Boost Converter

This paper presents comparative performance between Fuzzy Logic controller (FLC) and Proportional Integral Derivative controller (PIDC) on DC/DC Buck-Boost Converter. The evaluation of the output has been carried out and compared by software simulation using Matlab/Simulink. The controllers performance are compared based on dynamic respond of the controllers in term of rise time, settling time, overshoot, peak time and voltage deviations. DC/DC Buck-Boost Converter in this study is operated in Buck (step-down) and Boost (step-up) modes.

Artificial neural network-based forecast for electricity consumption in Malaysia

An essential element of electric utility resource planning is the long term forecast of the electricity consumption. This paper presents an approach to forecast annual electricity consumption by using artificial neural network based on historical data for Malaysia. It involves developing several ANN designs and selecting the best network that can produce the best results in terms of its accuracy. The network is developed by means of economical conditions and how the variables are going to be changed in the following years. After obtaining the most reliable model, ANN is used to forecast the electricity consumption. The developed ANN model yields very satisfactory results and as a result, the range of electricity consumption can be successfully obtained.

Modeling of power system dynamic devices incorporated in Dynamic Computation for Power Systems (DCPS) for transient stability analysis

An electrical power system consists of many individual dynamic devices connected together to form a large and complex dynamic system. To analyze the behavior of such devices, its physical model needs to be transformed into mathematical model before it can be solved on a computer. In electric utility practices, the aspect of modeling and computational methods for power system dynamic devices such as generator, exciter and governor has not been given much attention by many engineers because such tasks could be solved using commercial software packages. The two most important requirements of such software packages are; i) the correct input data and assumptions; and ii) the output results that can be analyzed and understood. Hence, there was a lack of understanding of the modeling and computational methods and also the limitations of the individual dynamic devices. This paper presents the fundamental modeling and computation methods related to power system dynamics and performing the power system transient stability analysis by using Dynamic Computation for Power Systems (DCPS) software package. This C/C++ based software has been developed for research purposes and can be used to simulate load flow and transient stability analysis. The Improved Euler Method has been employed in this software to solve the mathematical model of power system dynamic devices namely synchronous generator, turbine-governor and exciter. The results showed that this software has been successfully developed to perform the transient stability analysis. The effect of varying load demand on the critical clearing time, tCCT has been tested on heavily loaded IEEE 9-bus test system when three phase fault is applied at bus 5. The simulation results showed that the critical clearing time decreases linearly with increasing load demand.

Thunderstorm forecasting by using artificial neural network

Thunderstorm is a form of weather characteristic containing strong wind, lightning, heavy rain and sometimes snow or hail. It can be associated with a cloud type of cumulonimbus. Depending on its type, thunderstorm has great potential to produce serious damage to human life and property. Therefore, there are many sophisticated instrument used to record weather data such as Doppler radar and satellite. By using these data, based on the statistical, mathematical or soft computing technique can be done in order to predict the occurrence the weather characteristic. This project presents the application of artificial neural network (ANN) in forecasting the thunderstorm occurrence in Shah Alam based on the meteorological data. Therefore, several three-layer feed-forward back-propagation ANNs were developed in Matlab and each network was evaluated by using cross-validation technique. A network with the best performance in terms of its R-value was selected as the best design. Thus, the forecasting of thunderstorm occurrence can be successfully done.

Parallel Inductor Multilevel Current Source Inverter for Input Ripple Current Reduction in PEM Fuel Cell Applications

ABSTRACT In a power conditioning fuel cell system, the application of a single phase voltage source inverter (VSI) generates a second harmonic (100/120 Hz) ripple current. The harmonic current reduces life, efficiency and performance of the fuel cells due to hysteresis loss effects. This paper proposes current source inverter (CSI) with multilevel features to reduce the second harmonic (100/120 Hz) current ripple drawn from the Proton Exchange Membrane (PEM) fuel cell. The employment of energy recovery scheme in the proposed five-level multilevel current source inverter (MCSI) introduces a single switching state for each output current level. The proposed energy recovery scheme is able to balance the sharing inductor currents effectively. In addition, the proposed MCSI is also integrated with a boost DC current source in order to reduce the size of input DC link inductor and minimize the circuit structure for a reliable power conditioning PEM fuel cell system application.

Studies on control electronics implementation of single-phase single switch active power filter

This paper is concerned with control electronics for rectifier circuit topologies that control the rectifier input current waveshape to achieve unity power factor operation and very low current distortion levels. The control electronics uses discrete integrate circuits (ICs) for analogue control whilst the Peripheral Interface Controller (PIC) for digital control implementation. Comparisons are made on the performance of these control techniques. Selected simulation and experimental results were presented to verify proposed operation.

Computer implemented model of single switched single-phase parallel active power filter

This paper is concerned on a parallel active power filter for harmonic compensation of a single-phase system feeding non-linear load. An active current wave-shaping technique is proposed to mitigate the distortion current by injecting equal but opposite current to shape the pulsating nature of the supply current to a sinusoidal form and in-time phase with the supply voltage. In the proposed work only one power switch is employed to minimize cost, reduce switching stress and losses. The behaviour and operation of the proposed filter structure was examined through computer simulation.