The electrical network, essential to our society, frequently encounters disruptions from lightning strikes, resulting in material damage and power blackouts. Swift diversion of lightning currents to the ground is imperative to safeguard the grid. This study proposes a proportionality coefficient (K) to effectively distribute lightning current between grounding and network flow. The optimality of this coefficient depends on the tower grounding system resistances; lower resistances facilitate optimal distribution, enabling more current to flow to the ground. In the examination of the Djiri-Ngo power line in the Republic of Congo, grounding systems were optimised based on soil types. Three electrodes were used for clayey sand, while fifteen were employed for siliceous sand. Optimal coefficients were determined to be 0.86 for clayey sand and 0.81 for siliceous sand. These coefficients denote that 86% and 81% of the lightning current were directed to the ground, in contrast to non -optimal resistances (69% and 29% with a single grounding electrode). The experiments highlight the importance of adapting grounding systems to soil characteristics, rather than adhering to a uniform approach. Efficient diversion of lightning current to the ground is paramount for grid protection.

Lightning strikes can cause equipment damage and power outages, so the distribution system's reliability in withstanding lightning strikes is crucial. This research paper presents a model that aims to optimise the configuration of a lightning protection system (LPS) in the power distribution system and minimise the System Average Interruption Frequency Index (SAIFI), a measure of reliability, and the associated cost investment. The proposed lightning electromagnetic transient model considers LPS factors such as feeder shielding, grounding design, and soil types, which affect critical current, flashover rates, SAIFI, and cost. A metaheuristic algorithm, PSOGSA, is used to obtain the optimal solution. The paper's main contribution is exploring grounding schemes and soil resistivity's impact on SAIFI. Using 4 grounding rods arranged in a straight line under the soil with 10 Omega m resistivity reduces grounding resistance and decreases SAIFI from 3.783 int./yr (no LPS) to 0.146 int./yr. Unshielded LPS has no significant effect on critical current for soil resistivity. Four test cases with different cost investments are considered, and numerical simulations are conducted. Shielded LPSs are more sensitive to grounding topologies and soil resistivities, wherein higher investment, with 10 Omega m soil resistivity, SAIFI decreases the most by 73.34%. In contrast, SAIFIs for 1 klm and 10 klm soil resistivities show minor decreases compared to SAIFIs with no LPS. The study emphasises the importance of considering soil resistivity and investment cost when selecting the optimal LPS configuration for distribution systems, as well as the significance of LPS selection in reducing interruptions to customers.

The aim of this work is to analyze the effectiveness of Bentonite, Kenaf and Pine Wood mixtures as enhancement materials for grounding system purposes. Grounding systems are designed to dissipate high-magnitude fault currents to Earth and provide safety to persons working in or living near power system installations. They are also necessary to protect equipment from being damaged caused by lightning strikes. The safety and reliable operation of various applications in an electrical system is highly depending on the effectiveness of the grounding system installed which could be achieved with a low resistance path, and this can be obtained by employing grounding enhancement materials to the surrounding soil of the installation site. Hence, this is highlighted in this work where NEM mixtures grounding systems were installed at a site near to SGS, UPM with a high resistivity soil profile. Kenaf is a natural fiber that has been shown to be effective in improving the performance of grounding systems as it has a high conductivity and a high dielectric constant. This means that it can carry electrical current well and it can also store electrical energy. Kenaf is also a relatively inexpensive material, which makes it a cost-effective option. The unique properties of Bentonite, a clay material, and Pine wood, a natural insulator, make them promising options for improving grounding systems. Six grounding systems were installed with 100% Bentonite, 100% Pine, Bentonite and Pine Mix, Bentonite and Kenaf Mix, Pine and Kenaf Mix, and Reference grounding systems. A comparison was made between them using daily measured earth resistance from 2nd March 2023 until 10th July 2023, i.e. for 130 days. It was found that mixtures of Bentonite and Pine Wood performed better than the 100% Bentonite.

Grounding systems play a crucial role in protecting an electrical power system in order to provide a safe path for fault current flow dispersion, especially in the event of lightning to avoid damage towards electrical equipment and malfunctions of such system. Therefore, an effective grounding system should possess low current resistance, allowing the fault currents to flow in the least resistance path as quick as possible. There are several methods to obtain an effective grounding system with low earth resistance value. The most common is by introducing enhancement materials, which either natural or chemical based. Note that only Natural Enhancement Materials were employed in this work which include Bentonite, Gypsum, Vermicast, Coco Peat and Peat Moss, which were chosen based on their moisture retaining capabilities. This is due to the reason that Natural Enhancement Materials will not alter the characteristics of the surrounding soil and proved to be environment friendly, as opposed to the Chemical Enhancement Materials. A total of 15 samples with various ratios including 4 Soil Reference samples, i.e. from previous Grounding Systems 2016/2017, 2017/2018, 2018/2019 and 2019/2020, were tested. Moisture Retaining Test were conducted twice a week starting from 11th March 2022 until 10th May 2022, for a duration of 60 days once Volume Density Test was performed towards the 100% individually mixtures on day-0. It was concluded that the four best performed NEM mixtures in descending order were found to be Bentonite and Gypsum Mix A (86.72%), 100% Bentonite (86.59%), Bentonite and Coco Peat Mix A (79.69%), and Bentonite and Peat Moss Mix A (79.51%). Note that Bentonite ratio was more in Mix A compared to Mix B.

Grounding systems is a fundamental part in an electrical power engineering system. It is important for ensuring the safety of occupants, to protect electrical equipment from damage, minimize the risk of electrical hazards and maintain a stable system during both normal and fault conditions. Hence, a grounding system must provide a path for fault currents to safely dissipate into Earth while preventing electrical shock hazard, and reduce and limit the damage to any electrical equipment connected to it. However, traditional grounding systems may not always be able to provide the required level of conductivity, especially in high soil resistivity sites or in applications where high fault currents are anticipated. Resistivity of the surrounding soil is one of the parameters that can be easily manipulated for an efficient grounding system to be made available as it is influenced by factors such as geographical location, moisture content, temperature, and soil composition. In regions with poor natural soil conductivity or environments characterized by seasonal fluctuations in resistivity, the deployment of natural enhancement material is merged as a critical solution. In this work, three sites located around Universiti Putra Malaysia Serdang Campus, Selangor, MALAYSIA were tested for its soil resistivity. This is meant for grounding system installations with new natural enhancement material mixtures in the vicinity of vertical ground conductors. Site 2 with high resistivity and most homogeneous soil would be chosen to test the grounding system installations, while Site 1 with the lowest soil resistivity would be installed with Reference grounding system as comparison purposes. Note that a Reference grounding system is installed without any natural enhancement material mixture in the vicinity of the vertical ground conductor.