Partial Discharge Characterization based on Leakage Current Pulses Waveform for Contaminated Glass Insulator String

This paper deals with the analysis of partial discharge (PD) occurrences based on leakage current (LC) pulses distribution under different level of contamination. In this work, laboratory based contamination performance tests are conducted on four units of glass insulator string stacked in I-position. Results show that PD can be characterized (according to their occurrence with respect to the AC supply) as follows: corona discharge occurring dominantly in lightly contaminated insulators, surface discharge occurring dominantly in medium contaminated insulators and finally internal discharge occurring dominantly in heavily contaminated insulators. The ability to distinguish the type of PDs from the LC waveform could be used to monitor and predict the condition of the insulator. The outcome can be incorporated in a conditioning monitoring system

Transformer Fault Early Warning System Model Using GSM Network

This paper presents the design and implementation of amobile embedded system using an Arduino microprocessor to monitorand record key operational indicators of a distribution transformer,such as transformer oil level, temperature and vibration of adistribution transformer in a substation. If there is any abnormalityor an emergency situation, the system sends SMS (Short MessageService) messages to designated mobile telephones containinginformation about the abnormality of the mentioned parameters.Providing early warning of the abnormality of the distributiontransformer can be accomplished by shutting down the entire unitwith the aid on-line monitoring system integrates with Global ServiceMobile (GSM) Modem. Furthermore, the design generally consiststand-alone single chip microcontroller, modem and sensor packageslocated on distribution transformer site. In general, the design isdeveloped for the user to easily recognize the distribution transformerthat is suffered by any high vibration and rise in temperatures andlocated in remote or suburban area which is rarely and hard to reachfor manual monitoring. The ultimate objective is to monitor thetransformer oil level and temperature of 24 hours, 7 days a weekcontinuously besides the current and voltage parameter whichincluded in basis monitoring syste

Effect of broken skirts on voltage distribution along insulator strings

The existence of broken glass insulator as part of a complete string may alter the local voltage distribution. A finite element software is used to study the effect of broken glass insulator (stub) to the voltage distribution profile. In this paper we present the voltage distribution profile across single and ten units of glass insulator string with different locations. The results show that the presence of broken insulator under dry conditions and without contaminants affects the distribution profile of voltage. The local voltage distribution is certainly altered when the stub is present at any location in the string. However, maximum percentage increase in voltage is experienced when the stubs are located near to the ground (GND) end. This result helps to explain the ability of transmission line insulation system to operate satisfactorily even with the presence of stubs along the string

Surface Conditions Analysis of Polymeric Insulators Under Contamination Effects

A good polymer insulator can maintain the hydrophobic surface properties. However, polymer insulator is exposed to the environment which may lead to the deposition of rain water or factory oil. Oil is categorized as hydrophobic while water has a hydrophilic feature which when deposit on the insulator surface, it may affect the performance of insulator. Therefroe, this paper studies the effect of water and oil contamination on current density and space charge distribution along 15 kV polymeric insulators particularly ethylene propylene-diene monomer (EPDM) and silicone rubber (SiR). A three-dimensional model of polymeric insulator was designed using a finite element software to evaluate the current density and space charge distribution while the experimental works was conducted in the laboratory to measure the charge distribution only. The results reveal that both current density and charge distribution is affected depend on the conductivity of contamination conditions. Both results extracted from simulation and experimental is in agreement where the EPDM insulator have higher amplitude of charge compared to SiR insulator

Evaluation of residential grid-connected photovoltaic system as the potential energy source in Malaysia

Application of solar energy in Malaysia has been started in 1998. This country has a large potential of solar energy due to its location at equatorial region. The current energy consumption and demand in Malaysia is describes in this paper. The potential of solar energy in Malaysia is described together with the suitable photovoltaic construction. It also explains the plans conducted by Malaysia involving solar energy that covers investments and also projects involved such as Malaysia Building Integrated Photovoltaic (MBIPV). Simulation of grid-connected photovoltaic system in this study is performed using HOMER software. Finally, the potential of having a grid-connected PV system in a residential area is analyzed. The positive and negative findings in terms of cost and suitability of the system are explained

Potential of Residential Grid-Connected Photovoltaic System as the Future Energy Source in Malaysia

Malaysia has started the implementation of solarenergy harvesting in 1998. Located at equatorial region, Malaysia hasa large potential for solar energy. This paper examines the currentenergy consumption and demand in Malaysia. The potential of solarenergy harvesting in Malaysia is described together with the suitablephotovoltaic construction. It also explains the plans conducted byMalaysia involving solar energy that covers investments and alsoprojects involved such as Malaysia Building Integrated Photovoltaic(MBIPV). Finally, this paper analyses the potential of having a gridconnectedPV system in a residential area. The positive and negativefindings in terms of cost and suitability of the system are explaine

Fostering international collaboration in marine biodiversity sciences in the Asia-Pacific region

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Does ESG certification add firm value?

This paper examines the impact of environmental, social and governance (ESG) certification on Malaysian firms. The analysis shows that ESG certification lowers a firm's cost of capital, while Tobin's Q increases significantly. These findings, while consistent with existing studies in developed economies, demonstrate the value enhancement from corporate social responsibility disclosure by firms in emerging and developing nations. Overall, the study confirms the benefits to stakeholders from firms pursuing an ESG agenda

Study on partial discharge characteristics of generators : case study at Tanjung BinPower Plant, Johor, Malaysia

Power generation is a business that both satisfy industrial and consumer needs. Power generation technologies had emerged from conventional power plant which is denoted by conventional steam plant and evolved all the way to nuclear plant. While mechanical arrangements are usually unique and differ from a type of power plant compared to another, electrical assemblies are almost the same. Much anticipating factor is sizing of the electrical equipment. Among fundamental equipment that is a must have in a power plant is an electrical generator. In principle, generator is crucial equipment that needs a proper maintenance in order to produce a steady output stream. The objective of this study is to investigate partial discharge characteristics of 3 unit generators stator winding at Tanjung Bin Power Plant, Johor, Malaysia. We will compare the partial discharge characteristics of unit 10, 20 and 30 generators stator winding, respectively. Software designed by Iris LP will be used throughout these processes. The software-PDView will demonstrate graphical view of the partial discharge occurrence in the generator stator winding. Compiled data will be analyzed using Microsoft Excel in order to establish an evaluation of the generator stator winding. The analyzed results showed that all generators are in good condition

Charge distribution measurement of solid insulator materials: A review and new approach

A reliability of electrical energy supply could be disrupted by the build-up of space charge distribution within or on the surface of insulator. Preventive measures have been carried out since the earliest days of power transmission network invented till today to alleviate the space charge effect on electrical energy systems. Although the preventive measures have been taken greatly, there are inevitable factors especially environmental conditions that lead to the accumulation of space charge. Space charge which carries energy such as kinetic, heat and other forms is believed released these energies during the space charge accumulation process and subsequently distort the local electric field. Despite the numerous papers published on space charge investigation in polymeric insulation, there is an absence of thorough review papers on this topic as well as space charge effects on glass insulation. Hence, this paper provides a summary of charge distribution measurement within and on the surface of insulators along with a new approach to measure the space charge distribution on the surface of glass insulator strings. This knowledge will provide a contribution to the development of a new online space charge distribution measurement system for glass insulator string that will be more efficient, by utilizing the available technology for data transmission. This new approach also has the capability to monitor the condition of the insulator while energized and in service, thus the faulty insulators can be replaced without disrupting the distribution of electrical energy around the world