NORAZILA JAALAM | Universiti Malaysia Pahang (UMP) (original) (raw)

Uploads

Papers by NORAZILA JAALAM

AIMS electronics and electrical engineering, 2023

Electric vehicles (EVs) are an emerging technology that contribute to reducing air pollution. Thi... more Electric vehicles (EVs) are an emerging technology that contribute to reducing air pollution. This paper presents the development of a 200 kW DC charger for the vehicle-to-grid (V2G) application. The bidirectional dual active bridge (DAB) converter was the preferred fit for a high-power DC-DC conversion due its attractive features such as high power density and bidirectional power flow. A particle swarm optimization (PSO) algorithm was used to online auto-tune the optimal proportional gain (KP) and integral gain (KI) value with minimized error voltage. Then, knowing that the controller with fixed gains have limitation in its response during dynamic change, the PSO was improved to allow re-tuning and update the new KP and KI upon step changes or disturbances through a time-variant approach. The proposed controller, online auto-tuned PI using PSO with re-tuning (OPSO-PI-RT) and one-time (OPSO-PI-OT) execution were compared under desired output voltage step changes and load step changes in terms of steady-state error and dynamic performance. The OPSO-PI-RT method was a superior controller with 98.16% accuracy and faster controller with 85.28 s-1 average speed compared to OPSO-PI-OT using controller hardware-in-the-loop (CHIL) approach.

International Journal of Electrical and Electronic Engineering & Telecommunications, 2020

The increasing capacity of grid-connected photovoltaic (PV) over electrical power system might le... more The increasing capacity of grid-connected photovoltaic (PV) over electrical power system might lead to voltage sags which affected the consumers and industries. To improve this situation, a simple control strategy of reactive power control using neuro-fuzzy is proposed in this paper to enable voltage regulation in a single-stage gridconnected PV system. An Artificial Neural Network (ANN) model is trained until a satisfactory result is obtained. After that, the trained neural network is combined with fuzzy logic. During the abnormal condition, the reactive current is controlled to inject reactive power for grid support and voltage recovery purpose. The dynamic behaviour of the system will be analyzed under a three-phase fault condition via MATLAB/Simulink. The simulation result shows that the proposed control strategy using neuro-fuzzy controller is effective in compensating desired reactive power during such faults. The voltage profile of the system has shown at least 9% of increment in all case studies. A swift recovery on the voltage can be achieved as well since the voltage returns to steady-state immediately when the fault is cleared.  Index Terms-Low-voltage ride-through, grid-connected photovoltaic, neuro-fuzzy

Mathematical Problems in Engineering

In today’s world, the DG should not be disconnected in the event of a power outage but should ins... more In today’s world, the DG should not be disconnected in the event of a power outage but should instead remain linked to the grid and supported by reactive power. This can be accomplished by implementing the low voltage ride through (LVRT) with a proportional integral (PI) controller. As a result, the voltage profile can be enhanced. The PI controller, on the other hand, has drawbacks in that setting the gain takes a long time and results in an overshoot current on the grid, which could trigger the protection relay. To address this issue, this paper proposes employing a grey-wolf optimizer (GWO) to enhance the LVRT in a 5 MW three-phase grid-connected PV system. A MATLAB simulation was carried out then under a three-phase fault and load disturbance to verify the efficiency. It is found that, even with a 70% voltage sag, the PV system can remain connected to the electrical grid while minimising overshoot current on the grid side.

2022 IEEE International Conference on Automatic Control and Intelligent Systems (I2CACIS)

Lecture Notes in Electrical Engineering, 2021

4th IET Clean Energy and Technology Conference (CEAT 2016), 2016

Lecture Notes in Electrical Engineering, 2022

Page 1. A Fuzzy Logic Approach for Stator Resistance Estimation of an Induction Motor Norazila Ja... more Page 1. A Fuzzy Logic Approach for Stator Resistance Estimation of an Induction Motor Norazila Jaalam, Ahmed MA Haidar, Nor Laili Ismail, Rohana Abdul Karim University Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Kuantan, Pahang, Malaysia. ...

COMPUTATIONAL INTELLIGENCE APPLICATION TO MALAYSIAN PRACTICAL POWER SYSTEM Ahmed MA Haidar¹, Azah... more COMPUTATIONAL INTELLIGENCE APPLICATION TO MALAYSIAN PRACTICAL POWER SYSTEM Ahmed MA Haidar¹, Azah Mohamed², Ramdan Razali¹, Kamarul Hawari¹ Norazila Jaalam¹ University Malaysia Pahang¹ - UMP ... [8] A. Sallam, & A. Khafaga, Fuzzy Expert System ...

Renewable and Sustainable Energy Reviews, 2016

Recent interest in the integration of renewable energy sources (RES) into the power grid has rais... more Recent interest in the integration of renewable energy sources (RES) into the power grid has raised concerns in synchronization of the various RES. Grid variables such as voltage, phase angle and frequency should be continuously monitored to guarantee correct operation and synchronization of power converters connected to the power grid. Numerous synchronization methods have been presented over the years to address issues such as unbalanced condition and frequency variation. This paper presents a review of past studies on synchronization methods for grid-connected converters together with their control and modeling techniques. Various estimation techniques for phase angle, frequency and harmonic are discussed and examined. Key challenges for a smart and efficient synchronization are briefly overviewed and possible future works are also recommended. A consolidated review is the particular focus of this paper, as is the provision of information on the best method for synchronizing grid-connected converters.

An accurate estimation of stator resistance is very important especially during operation of an i... more An accurate estimation of stator resistance is very important especially during operation of an induction motor due to variation in the stator resistance and temperature of the working machine. This paper proposes a Neuro-fuzzy Technique (NFT) for an online estimation of the stator resistance under steady state operating conditions of an induction motor. The proposed technique is compared with the Proportional Integral (PI) estimator to see the effectiveness. The obtained results of applying the NFT for resistance estimation give better performance and high robustness than those obtained by the application of PI.

ipcsit.net

Vulnerability control is a problematic task for system operator who under economic pressure may b... more Vulnerability control is a problematic task for system operator who under economic pressure may be reluctant to take preventive action against very harmful contingencies in order to guarantee providing continued service. This paper presents fast and accurate load shedding technique based on neuro-fuzzy controller for determining the amount of load shed to avoid a cascading outage. A case study is performed on the IEEE 300-bus test system so as to validate the performance of neuro-fuzzy controller in determining the amount of load shed. The development of new and accurate techniques for vulnerability control of power systems can provide tools for improving the reliability and continuity of power supply. This was confirmed by the results obtained in this research of which sample results are given in this paper.

International Journal of Soft …, Jan 1, 2010

Abstract: Cost reduction is one of the main targets in power industry due to economic load dispat... more Abstract: Cost reduction is one of the main targets in power industry due to economic load dispatch problem and allocating loads to plants for minimum cost. The principal objective in economic dispatch of thermal generators in a power system is to determine the economic ...

Expert Systems with …, Jan 1, 2010

Vulnerability assessment and control of a power system is important to power utilities due to the... more Vulnerability assessment and control of a power system is important to power utilities due to the blackouts in recent years in many countries which indicate that power systems today are vulnerable when exposed to unforeseen catastrophic contingencies. A fast and accurate technique to assess the level of system strength or weakness is some of the essential requirements for maintaining security of modern power systems, particularly in competitive energy markets. This paper presents intelligent artificial techniques for vulnerability ...