Arshad Arshad

Glasgow Caledonian University | GCU · School of Computing Engineering and Built Environment

The arrival of virtual power plants (VPPs) marks important progress in the energy sector, providing optimistic solutions to the increasing need for energy flexibility, resilience, and improved energy systems’ integration. VPPs harness several characteristics to bring together distributed energy resources (DERs), resulting in economic gains and impr...

High voltage direct current (HVDC) transmission systems play a crucial role in addressing the challenges associated with the delivery of renewable energy by enhancing transmission capacity. However, their reliance on converters makes them susceptible to the issues related to current harmonics and voltage distortions. It is worth noting that, as of...

Transformers are indispensable components in any power networks, facilitating the delivery of generated electricity to consumers at the most secure voltage level. The insulation system of oil-filled transformers is critical for the safe operation of power transformers, although it undergoes consistent degradation over time. Similar to blood in a hu...

Abstract: As the focus tilts toward online detection methodologies for transformer oil aging, bypassing challenges associated with traditional offline methods, such as sample contamination and misinterpretation , fiber optic sensors are gaining traction due to their compact nature, cost-effectiveness, and resilience to electromagnetic disturbances...

In the realm of power delivery to end-users, transformers are indispensable, with their malfunctions leading to substantial economic, safety, and environmental repercussions. The need for persistent surveillance is accentuated for in-situ oil-filled transformers, given the potential degradation of oil and the emergence of related ageing by-products...

The Internet of Things (IoT) is a grid of interconnected pre-programmed electronic devices to provide intelligent services for daily life tasks. However, the security of such networks is a considerable obstacle to successful implementation. Therefore, developing intelligent security systems for IoT is the need of the hour. This study investigates t...

Transformers play a crucial role in power networks, ensuring that generated electricity is delivered to consumers at the safest voltage level, reducing losses, and enabling metering and grounding. The insulation system is critical for ensuring that the function of the power transformer is carried out safely, at the expense of its gradual deteriorat...

By coordinating the operation of regionally interconnected virtual power plants (VPPs), the growing penetration problem of renewable energy sources (RESs) into the power system can be addressed. This study presents an interactive trading cooperation model of regionally interconnected VPPs using bilateral contracts. The proposed model maximizes over...

Transformers play an essential role in power networks, ensuring that generated power gets to consumers at the safest voltage level. However, they are prone to insulation failure from ageing, which has fatal and economic consequences if left undetected or unattended. Traditional detection methods are based on scheduled maintenance practices that oft...

The power systems of today seem inseparable from clean energy sources such as wind turbines (WTs) and photovoltaics (PVs). However, due to their uncertain nature, operational challenges are expected when WT and PV energy is added to the electricity network. It is necessary to introduce new technologies to compensate for the intermittent nature of r...

The penetration of renewable energy sources (RESs) in the electrical power system has increased significantly over the past years due to increasing global concern about climate change. However, integrating RESs into the power market is highly problematic. The output of RESs such as wind turbines (WTs) and photovoltaics (PVs) is highly uncertain. Th...

Recently, networks are moving toward automation and getting more and more intelligent. With the advent of big data and cloud computing technologies, lots and lots of data are being produced on the internet. Every day, petabytes of data are produced from websites, social media sites, or the internet. As more and more data are produced, a continuous...

The Internet of Things (IoT) is a grid of interconnected pre-programmed electronic devices to provide intelligent services for daily life tasks. However, the security of such networks is a considerable obstacle to successful implementation. Therefore, developing intelligent security systems for IoT is the need of the hour. This study investigates t...

With the increasing volume of data transmission through insecure communication channels, big data security has become one of the important concerns in the cybersecurity domain. To address these concerns and keep data safe, a robust privacy-preserving cryptosystem is necessary. Such a solution relies on chaos encryption algorithms over standard cryp...

With the advent of high-speed and parallel computing, the applicability of computational optimization in engineering problems has increased, with greater validation than conventional methods. Pitch angle is an effective variable in extracting maximum wind power in a wind turbine system (WTS). The pitch angle controller contributes to improve the ou...

Silicone rubber is one of the most used outdoor insulation materials in the last few decades due to its improved performance in contaminated and humid conditions. The improved performance of silicone rubber insulators is due to their hydrophobic nature, however, the organic nature of silicone molecules makes them vulnerable to ageing and degradatio...

Internet of Vehicles (IoV) is an application of the Internet of Things (IoT) network that connects smart vehicles to the internet, and vehicles with each other. With the emergence of IoV technology, customers have placed great attention on smart vehicles. However, the rapid growth of IoV has also caused many security and privacy challenges that can...

Insulators play a critical role in healthy transmission under the influence of operational stresses (OSs). OSs include environmental stresses (ultraviolet-radiations, seasonal heat and humidity variations, and pollution (inert and active), etc.) and electrical stresses (electric field distribution, corona, etc.). OSs can deteriorate insulators, jeo...

Understanding the flashover performance of the outdoor high voltage insulator has been in the interest of many researchers recently. Various studies have been performed to investigate the critical flashover voltage of outdoor high voltage insulators analytically and in the laboratory. However, laboratory experiments are expensive and time-consuming...

There is a vital need to understand the flashover process of polymeric insulators for safe and reliable power system operation. This paper provides a rigorous investigation of forecasting the flashover parameters of High Temperature Vulcanized (HTV) silicone rubber based on environmental and polluted conditions using machine learning. The modified...

The evolution of wireless and mobile communication from 0G to the upcoming 5G gives rise to data sharing through the Internet. This data transfer via open public networks are susceptible to several types of attacks. Encryption is a method that can protect information from hackers and hence confidential data can be secured through a cryptosystem. Du...

Aerial photography involves capturing images from aircraft and other flying objects, including Unmanned Aerial Vehicles (UAV). Aerial images are used in many fields and can contain sensitive information that requires secure processing. We proposed an innovative new cryptosystem for the processing of aerial images utilizing a chaos-based private key...

Renewable energy resources are preferred as compared to conventional energy resource due to their environment friendly nature. Micro-hydropower plant is one of the best renewable energy sources that provides electricity to hilly and rural areas. Micro-hydropower plants are mostly installed at natural heads and runoff rivers. Lack of a reservoir at...

With the advancement in digital technologies and the demand for secure communication, there is an increased interest in the design and implementation of reliable image encryption schemes. This paper presents a thorough review of chaos theory and its application in image encryption schemes. Due to ergodicity and initial key sensitivity, chaos-based...

This paper presents an efficient technique to switch on and off the dummy loads in an electronic load controller effectively. The electronic load controller is an essential part of pico and micro hydro-power generating units that provide stable and high quality electric power to consumers. The magnitude and frequency of the output voltage is kept s...

This article presents a new technique for determining accurate values of resonant frequency and quality factor pertaining to the split-ring resonator. Different conducting shield materials have been used around a copper split-ring. The split-ring has been designed to operate at about 2.1 GHz. Various equations were worked out earlier to determine t...

Ageing and degradation of silicone rubber insulators in contaminated environments is a major concern due to their organic nature. Understanding the flashover process of silicone rubber insulators under contamination is very important and needs standardized tests and procedures. Surface resistance measurement can be used as an indication of ageing a...

Medical consultants and doctors store and update patients confidential information on Internet cloud computing platforms. These days, securing medical images from eavesdroppers is one of the most challenging and significant research areas. Due to various attacks from eavesdroppers, medical images need to be store and send in the encrypted format. I...

Dry band formation on the surface of outdoor insulators is one of the main reasons leading to flashover and power outages. In this paper, a dynamic arc model is proposed for single and multiple dry bands configuration to predict the critical flashover voltage for silicone rubber outdoor insulators. An arc is modelled as a time dependent impedance c...

The deposition of ice, snow, pollution or their mixtures on the surface of outdoor insulators may severely affect their performance, resulting in electrical and or mechanical failures. Various preventative methods are used to minimize the problems of ice and pollution build up on the surface of outdoor insulators. In the last few decades, advanced...

This paper investigates the flashover and ageing behavior of silicone rubber insulators under various contamination and dry band conditions. Effect of pollution severity, leakage distance and dry band location on the flashover characteristics of silicone rubber insulator was investigated. Flashover voltage and electric field distribution were measu...

Chemical changes along the surface of silicone rubber material due to partial arcs and dry band arcing were studied in this paper. Rectangular samples of silicone rubber were used for experiments and pollution was applied using the modified solid layer method based on IEC 60507. All tests were carried out in a climate chamber having temperature, hu...

Silicone rubber insulators are replacing the conventional ceramic and porcelain insulators rapidly in power transmission and distribution industry. Very limited field knowledge is available about the performance of silicone rubber insulators in polluted and contaminated environments and therefore need further investigation. A comprehensive analysis...

Silicone rubber insulators are replacing the conventional ceramic and porcelain insulators rapidly in power transmission and distribution industry. Very limited field knowledge is available about the performance of silicone rubber insulators in polluted and contaminated environments and therefore need further investigation. A comprehensive analysis...

Electrical field distribution along the insulator surface is considered one of the important parameters for the performance evaluation of outdoor insulators. In this paper numerical simulations were carried out to investigate the electric field and potential distribution along silicone rubber insulators under various polluted and dry band condition...

This paper investigates the effect of pollution severity and relative humidity on the performance of silicone rubber and ethylene propylene diene monomer (EPDM) insulators. Rectangular samples of silicone rubber and EPDM were used for the tests. The ramp test method was used to measure flashover voltage and leakage current at different climate cond...

This paper investigates the formation of dry bands along a rectangular silicone rubber surface and their effect on the flashover characteristics. Plate samples of silicone rubber were used for experiments and pollution was applied using the modified solid layer method based on IEC 60507. Dry bands of various widths were inserted at the ground end,...

Outdoor insulators are exposed to various types of stresses during service conditions (Electrical, Mechanical and Environmental). Design and selection of outdoor insulators is based on their performance under contaminated and humid conditions. Pollution deposition on outdoor insulators is a natural phenomenon and depends on various factors (Insulat...

Flashover behaviour of silicone rubber insulators were analysed under contaminated conditions in this paper. The modified IEC 60507 Standard was used to simulate pollution deposition on the insulator surface. Experiments were carried out at different pollution level and changing leakage distances to investigate the behaviour of silicone rubber insu...

Electric field distributions along a polymeric insulator under wet and contaminated conditions were studied in this paper. To study the effect of pollution layer conductivity and thickness on the electric field distribution along a standard polymeric insulator, simulations were carried out with commercial simulation package Comsol Multiphysics. Pol...

Electric field distribution along an insulator surface is of prime importance for the long term performance of insulators. In this paper electric field and potential distribution along a standard 33 kV polymeric insulator were investigated under different pollution conditions. Effect of voltage type and polarity on the electric field and potential...

To study the effect of dry band location on electric field distribution of polymeric insulators, simulations were carried out using Comsol Multiphysics. The effect of dry band along a polymeric insulator at shed, core and junction of core and shed regions on the electric field distribution was investigated. Pollution was modelled as a 2-mm uniform...

To study the effect of pollution level on electric field distribution of polymeric insulators, simulations were carried out using Comsol Multiphysics. The effect of light, medium, heavy and very heavy pollution on the electric field and potential distribution was investigated. Pollution was modelled as a uniform conductive water layer on the insula...

Power outages due to flashover on outdoor polluted insulators are a major concern for power transmission and distribution industry. Under polluted conditions layer contains various contaminants, soluble and non-soluble. Soluble contaminants dissociate in the presence of water and become conductive. Leakage current is driven along this conductive su...

During last few years, transmission of digital multimedia data (images, audios and videos) over Internet, wireless cell phones, television broadcasting etc., has been significantly evolved. The provision of security to store and transmit data with confidentiality, integrity, and authentication for multimedia data over wireless medium is attaining i...

Power outages due to pollution flashover of outdoor insulators are a major concern for power transmission and distribution industry. With the increase in power consumption large power generating units are installed at remote location from the urban areas. To transmit power in bulk a reliable transmission system is needed to be in place. The reliabi...

This paper presents the electromagnetic field expressions for 3D cassegrain system embedded in a bi-isotropic chiral medium. Mathematical formulation of Maslov is used to find the field expressions in the focal region. Effect of chirality (both the week and strong) on focal region fields is analyzed. It is seen that when the chirality effect is wea...