An Overview of Covid-19 Impact on Power Grid Operation in Malaysia

The first notable impact of COVID-19 on the states and regions connected to the National power grid in peninsular Malaysia was a decreased ramping of load demand, particularly during usual peak demand hours. Due to the uncertainty in the transmission rates of this pandemic, the electricity demand will continue to fluctuate because of the change in human behavior and lifestyle globally

Experimental study of using renewable energy in Yemen

During the last decade, there has been an increased interest to develop renewable energy technologies that could contribute to ever-increasing energy needs. This paper proposes a new PV array-wind-diesel generator hybrid system model to determine the optimal configuration of power systems relevant to different regions in Yemen, Sana’a and Aden. Various renewable and nonrenewable energy sources, energy storage and their applicability in terms of cost and performance are discussed. The collected data for the wind, solar radiation and diesel price were obtained from Civil Aviation & Meteorology Authority in Yemen. The Sensitivity analysis was carried out using Homer program. The results show that wind-diesel-battery model is the most suitable solution for both regions in term of the economic performance

An accurate algorithm of PMU-based wide area measurements for fault detection using positive-sequence voltage and unwrapped dynamic angles

Modern power system requires advanced and intelligent sensors-based protection such as a Phasor Measurement Unit that can provide faster, accurate, and real-time data acquisition. The aim is to allow accurate action-based performance for analysts in monitoring the transmission lines so that rapid actions can be taken during abnormal circumstances before the blackout occurs. Among different algorithms, this study focuses on modelling the non- recursive phasor estimation method in a power Simulink environment for a standard test system equipped with a developed algorithm to detect the fault zone. The algorithm includes an index for faulty bus classification based on the positive-sequence voltage measurements of the pre-fault and post-fault conditions, where the bus with a maximum differential percentage is identified as a faulted bus. An important differentiation of this work is that the proposed algorithm can coordinate with all phasor measurement units to accurately determine the faulty line using the index of unwrapped dynamic phase angles. Furthermore, the robustness of the indices is analyzed in the presence of sudden load change, measurement noise, and during nonlinear high-impedance faults. The performance of the comprehensive algorithm is investigated on the IEEE 9-bus and 39-bus standard test systems by applying different faults scenarios, considering several factors such as fault inception angles, line-fault resistance, ground-fault resistance. The comparative studies have shown that the proposed indices can play a significant role in segregating the fault and non-fault conditions, as they are needed to supervise the appropriate relays for enhancing the overall security of the power grid

A Market Framework for Energy Bidding Decision Making Strategy to provide a Competitive Mechanism in the Context of Deregulated Electricity Market

In the modern power grid operation, the regulatory goal of the market is to provide continuous electricity supply to the customers with reasonable energy prices. The current structure of energy market in Malaysia follows the single buyer market model, where the generation is procured solely by a single utility with a limited competition, which is not effective in lowering the electricity prices. This paper proposes a market framework for competitive strategies to achieve maximum benefits of the power grid in Sarawak, Malaysia while the optimal bidding in the day-ahead market is assessed. Game theory with the non-cooperative scheme is applied for the electricity market comprising various participants. The performance of the proposed approach is evaluated using a practical power grid with data of the electricity market obtained from available sources. The feasibility of electricity market deregulation in Sarawak is proven to be effective, as the proposed framework can provide insight into the generated revenue of energy producers in a fair and competitive market environment

A Market Framework for Energy Bidding Decision- Making Strategy to provide a Competitive Mechanism in the Context of Deregulated Electricity Market

In the modern power grid operation, the regulatory goal of the market is to provide continuous electricity supply to the customers with reasonable energy prices. The current structure of the energy market in Malaysia follows the single buyer market model, where the generation is procured solely by a single utility with limited competition, which is not effective in lowering electricity prices. This paper proposes a market framework for competitive strategies to achieve maximum benefits of the power grid in Sarawak, Malaysia while the optimal bidding in the day-ahead market is assessed. Game theory with the non-cooperative scheme is applied for the electricity market comprising various participants. The performance of the proposed approach is evaluated using a practical power grid with data of the electricity market obtained from available sources. The feasibility of electricity market deregulation in Sarawak is proven to be effective, as the proposed framework can provide insight into the generated revenue of energy producers in a fair and competitive market environment

Feasibility Analysis of Implementing Hybrid Powered Electric Vehicle Charging Stations in Sarawak

— The transportation sector in Sarawak completely depends on fossil fuel which produces a high quantity of greenhouse gases. A suitable design of charging stations for electric vehicles (EVs) equipped with grid-integrated renewable energy resources (RERs) can help in addressing this issue. This paper proposes to enhance the execution requirements of the hybridpowered electric vehicle charging stations (EVCSs) in Sarawak. A generalized approach for modelling a renewable energy-based hybrid microgrid equipped with EVCS is presented in detail. Four types of microgrid configurations with biomass and solar photovoltaic (PV) systems have been studied to find the optimal size of each component feasible for EVCS. Each design of the hybridpowered EVCS has been analyzed in terms of economic and environmental viability using the climate data with associated monetary data. The analysis shows that the cost of lowering emission to zero is directly proportional to the total net present cost (RM 259,088) when using PV microgrid-powered EVCS. The outcome of this paper provides insight for policymakers on the technical and financial benefits of EVCS deployment. It also promotes the industry of Plug-in Electric Vehicles (PEVs) in Malaysia

Development of Thiophene Compounds as Potent Chemotherapies for the Treatment of Cutaneous Leishmaniasis Caused by Leishmania major

Leishmania major (L. major) is a protozoan parasite that causes cutaneous leishmaniasis. About 12 million people are currently infected with an annual incidence of 1.3 million cases. The purpose of this study was to synthesize a small library of novel thiophene derivatives, and evaluate its parasitic activity, and potential mechanism of action (MOA). We developed a structure–activity relationship (SAR) study of the thiophene molecule 5A. Overall, eight thiophene derivatives of 5A were synthesized and purified by silica gel column chromatography. Of these eight analogs, the molecule 5D showed the highest in vitro activity against Leishmania major promastigotes (EC50 0.09 ± 0.02 µM), with an inhibition of the proliferation of intracellular amastigotes higher than 75% at only 0.63 µM and an excellent selective index. Moreover, the effect of 5D on L. major promastigotes was associated with generation of reactive oxygen species (ROS), and in silico docking studies suggested that 5D may play a role in inhibiting trypanothione reductase. In summary, the combined SAR study and the in vitro evaluation of 5A derivatives allowed the identification of the novel molecule 5D, which exhibited potent in vitro anti-leishmanial activity resulting in ROS production leading to cell death with no significant cytotoxicity towards mammalian cells

Voltage Regulation Planning Based on Optimal Grid-Connected Renewable Energy Allocation Using Nature-Inspired Algorithms to Reduce Switching Cycles of On-Load Tap Changing Transformer

Due to the non-deterministic and probabilistic qualities of renewable energy resources (RER), integrating these resources has posed a challenge for energy companies and government policy planners. Hybrid power systems require frequent voltage regulation to address the changes in renewable generation and facilitate voltage management. This leads to an increment in the operating time of the tap changer in the power transformer, thus resulting in accelerated degradation of the on-load tap changer (OLTC) device. The primary focus of this paper is to optimally manage the penetration level of renewable generation while maintaining the minimum time for proper operation of voltage regulation devices. Accordingly, the major contribution of this paper is to address the switching cycle issues of the on-load tap changing transformer. Initially, a framework is proposed to optimize the location and size of renewable power generation using a multi-objective cuckoo search optimization algorithm. The main goal here is to reduce power losses and tap changer operations while improving the system voltage profile under different levels of renewable energy penetration. The optimization problem takes into consideration the fluctuating nature of wind speed and solar irradiance for sunny and cloudy days over 24 h. The framework has been applied to the IEEE 57-bus and 118-bus systems with different load levels. The performance of the proposed approach has been benchmarked by comparing it with the genetic optimization algorithm to identify the higher potential buses for renewable generation allocation. The cuckoo search algorithm (CSA) shows outstanding results in reducing the number of switching cycles to about (37 – 43) % whereas the genetic algorithm (GA) only (17 – 18). In this sense, the number of changes in tap position when using the CSA is 1956 for sunny days and 1763 for cloudy days compared to GA 2558 for sunny days and 2547 for cloudy days. The voltage profiles for both algorithms are maintained in the range of (1.06 and 0.94) per unit. The results affirm the effectiveness of the proposed approach in determining the optimal placement and size of RER with voltage profile improvement and reduction in the switching cycles of OLTC

Parameters evaluation of Unified Power Quality Conditioner

The term of “Power Quality” is used to describe the electromagnetic phenomenon in variations of voltage and current in the power system. Most power quality disturbances can come from the facility itself, such as large loads turning on simultaneously, improper wiring and grounding practices, the start-up of large motors and electronic equipments that can be both a source and victim of power quality phenomena or from externally generated, for example, lightning strokes on the power lines. Currently, there are so many industries using a high technology for the manufacturing and requiring a high quality of power supply. Therefore, the paper is focusing mainly on power quality disturbance and the technique used to improve the quality of delivered power such as Unified Power Quality Conditioner (UPQC). A comprehensive analysis was performed on the parameters that affecting the performance UPQC and the MATLAB software has been used to simulate the test system. Based on the results of analysis, it can be confirmed that UPQC is an effective technique for quick improvement of power quality