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In developing countries like India, most of the low voltage distribution lines feeder are connected via overhead power lines. Such distribution systems, including radical type and low voltage Interconnected networks, face difficulties in fault detection and localization as compared with high voltage transmission systems. One such fault is the broken conductor of live wires, which could cause high impedance current to flow on the ground or object. These faults usually produce very low fault currents, due to low voltage or dry areas, that are usually not detectable by the feeder conventional over-current protection schemes or by the HIF fault detector. As a result, fault detection in Low voltage (LV) overhead lines, due to open (or broken) conductors, is the most challenging problem in interconnected networks as compared to radical feeders. The aim of this paper is to identify a new method to detect such broken conductors in interconnected LV distribution and correctly automates the circuit breaker during faults. The proposed broken conductor fault detection method judges fault based on multiple information to increase accuracy and reliability of trip signal. The trip signal, based on the calculated measurements from the fault finding devices, will be provided to the circuit breaker. Finally, the proposed intelligent electronic devices installed at the bus Circuit Breaker Validates the trip signal before the power completely goes off. Several test cases were simulated to demonstrate the effective results.

Background: There has been rising concern amongst the public regarding their home's proximity to high tension power transmission lines. The primary cause of fear is the impact of the electromagnetic interference (EMI) radiation on the nearby occupants' health. Despite the presence of national permissible limits of EMI radiation, there is still lack of information with regards to the EMI radiation of the types of power lines configuration in Malaysia. Methods: The electric and magnetic fields of several selected power transmission lines were simulated using the EMFACDC software program from the recommendation ITU-T K.90. Five types of power transmission lines available in Malaysia are considered. Results: It was found that the simulated electric and magnetic field levels at all the power lines' right of way (ROW) boundary complies with the prescribed exposure limit. However, the electromagnetic fields (EMF) level increases significantly as the separation distance is reduced from 30m. For a more conservative approach, the ROW can be set at 30m across all transmission voltage level and corridor area condition. Conclusion: It can be concluded that Malaysia's power transmission lines are within the prescribed exposure limits. To further minimize the electric and magnetic field level, it is recommended that the residential building should be built at least 30 meters away from the power transmission lines, especially for the 275kV double circuit, 275/132kV quadruple circuit, and 500kV double circuit lines.

Electrical engineers often find the process of designing the earthing system of substations to be tedious, arduous and time consuming. Mobile apps development and usage has been on the rise of late due to the high availability of smart phones and Internet of Things. In terms of electrical earthing system design, there are very few applications available which are neither helpful nor informative. Hence, this paper outlines the development of a mobile application which is able to assist and ease electrical engineers’ design process. Functionality and validity of the app has been verified by comparing calculations obtained manually and by the app. Hence, this app can be used for the design and verification of an earthing system.

Malaysia is rapidly expanding the generation capacity of solar power through large scale solar (LSS) projects with the aim to achieve 20% renewable energy mix by 2025. This has motivated many solar industry players to explore the usage of solar PV with single axis tracker (SAT) system. However, many are still hesitant due to the lack of understanding on the comparative performance between fixed mounted solar PV with solar PV with SAT system. This paper aims to provide a comparative analysis on the performance of both systems. Simulation using PVSyst 6.83 was performed in five potential LSS sites spread across Peninsular Malaysia in Perlis, Kelantan, Pahang, Selangor and Johor with the same installed capacity of 10.32MWp. The energy yield and capacity factor for 21 years were simulated. On the average, it was found that SAT outperforms fixed mounted solar PV system by 15.08% based on their performance on their first year operation.

MS IEC 62305: Protection Against Lightning standard serves as the main reference for lightning risk assessment and lightning protection design and installation in Malaysia. Lightning risk assessment is complex and complicated to be used manually. A computer tool or software could simplify the work in lightning risk assessment. A template was developed in Microsoft Excel for lightning risk assessment. The development focused on features such as userfriendly interface, multiple zone and service calculation capability, comprehensive, informative, and able to suggest protection measures. All calculations and parameters for risk calculation were identified from MS IEC 62305-2: Risk Management. The calculations and interactive user interface were made using Excel’s built in functions and coding in VBA. The template was validated through comparison of results between the template, MS IEC 62305-2, and other software such as SIRAC and RISK in three different case studies. In all three case studies, the template achieves results similar to the results in IEC 62305-2.

Practical challenges of electrical earthing in both steady and transient states have been revisited. By analyzing the cases based on theoretical and practical aspects, engineering guidelines are proposed to develop suitable solutions. Less complicated cases can be approached with various electrode configurations such as multiple ring, antenna, crow-foot and centipede arrangements. Distributed earthing arrangements treated with backfill materials are suitable for the sites with extremely high resistive soil. Clay based backfill materials such as bentonite-mix give corrosion and erosion protection for the electrodes in highly acidic, alkaline, saline and sulfur-rich environments apart from reducing the low frequency resistance. On-rock sites such as transmission and communication towers are better approached with concrete-based earthing systems in both cases of power and lightning protection earthing. Extreme cases of soil instability have been identified and discussed. The suitability of vertical and horizontal electrode components as well as copper and steel electrodes under various soil conditions is also discoursed. For most cases, we recommend all types of earthing systems to be integrated, however, properly coordinated system of Surge Protective Devices (SPDs) should be incorporated in such integrated earthing system.

The final-year project (FYP) is considered to be one of the most important learning experiences in an engineering undergraduate education. It is mandated by engineering accreditation bodies worldwide as a compulsory module in the engineering curriculum. For most fresh graduate engineers, their final-year project experience will be the most vivid of all their recent memories when they recall their engineering education experience. This is due to the immense challenge the students face by undertaking for the very first time an individual, highly complex, open-ended research work with tight deadlines to meet and high expectations to attain on their own, albeit under the guidance of their supervisors. As such the FYPs’ delivery and assessment process offer strategic opportunities for engineering educators to add value to an undergraduate engineer’s training provided that it is designed and implemented with a clear intent. This paper documents the assessment approach adopted by School of Engineering, Taylor’s University, for the FYP module which is divided into the FYP1 and FYP2 modules covering two semesters. This assessment process is distinct from the practices at many other equivalent institutions in that it has as much as 6 assessment components for each module, assessors other than the supervisor contribute the bulk of the marks, timely feedback from assessors to students is fully integrated into the assessment process to facilitate learning and students are required to participate in a research conference which is also made into one of the assessment components. For this undergraduate conference, the students’ FYP research papers are reviewed by external reviewers from other universities and assessed and awarded marks by them. A detailed description of each assessment component followed by an evaluation of how each assessment component adds value to the students’ learning for both the FYP1 and FYP2 modules is discussed.

Metallic part would play an influential role in the case of probability of lightning strikes. An experimental study has been done to find out the effect of the presence of floating electrode on the body during thunderstorm. Although, it is clear that a small metal part on the body or in vicinity does not have effect during direct strike, the effects has been examined only in the case of side flashing. SPSS has been used to check the statistical significance of the probability. According to the result, floating electrode may shorten the gap distance of the struck point and a human body thus increasing the probability of lightning side flashing. The test has been done covered floating electrode (insulated) as well. Thus, it is recommended to either remove or isolate the metal parts during thunderstorm.

The value of soil resistivity is an essential pre-requisite in designing an electrical grounding system. The current practice, as advocated even by national/international standards involves taking the average soil resistivity of the site as the parameter to be considered in designing the grounding system. This study shows that average soil resistivity may lead to significant overestimation or underestimation in the designing process as the localized soil resistivity may significantly differ from the average soil resistivity of the entire site. At least 14% difference between average and localized soil resistivity were obtained base on measurements done on five locations. Therefore, it is suggested that electrical engineers who design grounding systems should first identify the locations where the components of the grounding systems will be installed. Then, the localized soil resistivity at that particular point should be measured and the sizing and geometry of the grounding electrode should be designed accordingly.

Effects of surrounding environment of grounding electrode locations on the performance of overall grounding system has been studied. Copper rods were buried at 25 different locations with various environmental settings and their respective variations in grounding resistance were monitored for up to 4 months. It was found that there is a clear dependence of grounding resistance on the condition of surrounding environment, in addition to the average soil resistivity. Installation of grounding electrodes near running waterways, huge trees as well as slopes should be avoided wherever possible as the ground resistance of electrodes in such environments may fluctuate significantly with time.

Grounding issues related to lightning currents have been addressed giving special attention to recommended practices in IEC 62305 (2010). Unambiguous recommendations are needed for the requirement of type A system or type B system or both systems for a given installation. Specifications of the length of conductors, based on the level of protection, were critically analyzed emphasizing the human risk related issues. Calculations reveal that at Level III and IV, the specified lengths of type A conductors may give step potentials, especially in highly resistive soils that may drive currents through human beings in the vicinity, exceeding lethal energy. Furthermore, specification of the limiting value of resistance for transient grounding systems may lead to hazardous situations as the difference between frequency dependent impedance and low frequency resistance may increase to very high values at Mega Hertz range where lightning energy spectrum has significant amplitude. Covering of a sizable surface area surrounding the grounding conductors with insulation material, is recommended as a practical solution to this issue.