Conference Publications
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PublicationSimulation analysis for 33 kV porcelain insulator string based on room temperature vulcanize coating(IEEE, 2023)Porcelain insulator is widely used in high voltage (HV) transmission lines due to its high mechanical strength, performing well on heat and aging resistance. However, porcelain insulator string is always exposed to environmental contamination. The presence of accumulation contamination on the porcelain insulator string surface reduces the electrical performance and causes insulation failure in transmission and distribution lines. Literature has shown that the conventional method to prevent contamination is limited to periodically water washing and silicone grease, involving some limitations in practice from the technical and economic point of view. Therefore, this research investigates the performance of porcelain insulator string due to the contamination effect based on Room Temperature Vulcanize (RTV) coating in 33 kV transmission line system. The four-unit porcelain insulator string in 2-D form was first developed using computer-aided design (CAD). Electric field and voltage distribution results were analysed using finite element method (FEM) software. After adding RTV coating, the percentage decrement of electric field distribution value is 9.73% from the study. This has proven that the porcelain insulator string with a significantly lower electric field distribution may protect the transmission lines from a higher risk of corona or even flashover.
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PublicationThe impact of cavity size on electric field distribution and PD inception voltage in epoxy-resin insulation(IEEE, 2023)Cavities in insulation systems of active high voltage (HV) equipment affect their performance, reliability and useful life periods. Cavities serve as flash points for enhanced field activity leading to ageing from partial discharge (PD) events and subsequent breakdown of the insulation material. In this paper, the impact of cavity diameter on the electric field distribution as well as on PD inception voltage are investigated in an Epoxy-resin insulation sample. A 3D adequate model of the sample with a spherical cavity was created and simulated in COMSOL for different cavity sizes and applied voltage stresses respectively. The simulation results indicate that both field distribution and the PD inception voltages are strongly influenced by cavity size as well as the applied voltage magnitude. The electric field intensity was observed to be higher in cavities with smaller diameter relative to the insulation bulk, while the inception voltage decreases with increase in the cavity diameter and vice-versa.
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PublicationSmart solar safety worker helmet using accelerometer and GPS sensor(Springer, 2023)In construction projects, safety is a big issue. There is not an effective option to overcome the situation. The safety of the public is jeopardized during the construction process. Some incidents happen when people fall from great heights and go unreported, resulting in death due to a lack of medical assistance. However, the numbers of deaths could have been prevented. This research aims to create smart wearable gadgets, such as a safety helmet that use a variety of sensors such as solar, accelerometer, and GPS sensor to improve worker safety. The IoT-based gadgets assist in detecting worker falls and sending notifications for emergency assistance. The system starts with solar energy charging the battery and then when the accelerometer sensor detects any falls, the notification will be sent to the Blynk. Meanwhile, GPS sensor detects the location of the worker and shows in the Blynk. As a results, the prototype has been tested in a variety of situations and proved to be extremely accurate which the improvement is almost 3.3%.
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PublicationPerformance of energy encryption for medium field wireless power transfer system by optimization switching frequency(Springer, 2023-07)Encryption is a very important technique used to protect energy transmission channels from unauthorized receiver. It can be utilized to transmit data securely over the wireless medium. Encryption techniques of wireless power transfer (WPT) are important in the research on the effects of security key for security of energy transfer to the authorized receiver. The energy encryption scheme of WPT is proposed to chaos theory. Chaos theory is applicable to the logistic map to propose as a security key to chaotically regulate the switching frequency. Furthermore, chaos theory characteristic affects power and distance performance. Therefore, this paper investigates mainly effective power based on mobile charging application. This research is focusing on the performance of energy encryption in medium field for wireless power transfer system by optimization switching frequency. This research is dedicated to the performance of energy encryption for medium field wireless power transfer system based on mobile charging application. The optimization to transport the power in this research based on power is 10 W. The research utilized MATLAB simulation to compare the performance.
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PublicationFeasibility study of seven-level two-stage cascaded switch-diode multilevel inverter under different inductive loads(AIP Publishing, 2024-02)Two-stage cascaded switch-diode multilevel inverter (TSCSDMI) is a modified cascaded H-bridge multilevel inverter (CHMI) with a reduced number of active power semiconductor switches. The TSCSDMI topology is constructed with two main circuit stages. The 1st stage consists of several cascaded switch-diode basic cell modules and a bypassing active power semiconductor switch, whilst the 2nd stage consists of a H-bridge module. The implementation and performance of a five-level TSCSDMI have been reported in the literature. However, the feasibility of the TSCSDMI with a higher number of voltage levels under different inductive loads has not been fully explored. Hence, this paper evaluates and analyzes the performance of seven-level TSCSDMI operating under different inductive. The analysis is conducted using PSIM simulation and the simulation results suggest that the seven-level TSCSDMI is not suitable for heavier inductive loads. For example, the output voltage waveform of seven-level TSCSDMI starts to deteriorate with an undesired voltage spike when the displacement power factor of an inductive load is equal to 0.90 or lower. The undesired voltage spike tends to worsen the total harmonic distortion (THD) of the output voltage waveform. Hence, for minimal THD operations, a seven-level TSCSDMI should be employed for applications with light inductive load.