Types and Configurations of EHV/EHV and EHV/HV Substations The Role of EHV/EHV and EHV/HV Substations in Transmission Network EHV/EHV and EHV/HV[1] substations are an important element of the electricity transmission network of a country or of a large area of a country and their functions are: Interconnection of power plants of the national or area electrical grid. Step up and …
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Electrical Protection Units And Systems Introduction to Electrical Protection Systems HV, MV and LV[1] electric installations and equipments are subjected to internal and external faults that can cause serious damages in persons and other equipments. To avoid and to minimize the consequences of those faults protection devices associated to equipments that are able to break electric current are required. For …
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Maintenance of Power Transformer – Transformer Diagnostic and Monitoring Introduction Being transformers static machines without any moving and turning parts, they are very reliable machines, and if maintained properly, can last for 40 years or more. Also they do not trip or blow when oven-stressed (except under extreme conditions), transformers are frequently overloaded and allowed to operate well beyond its …
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An Introduction to Insulating And Dielectric Materials Definition of Insulating and Dielectric Materials An electrical insulating material can be defined as the material that does not allow electric current to pass through it. For electrical applications a particular category of insulating materials is used to separate electrically the conducting parts of equipment from each other and from earthed and “no …
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Basic Requirements for Transformers Fire Protection System By: Manuel Bolotinha Causes of Fire in Transformers Excessive overheating, extremely severe short circuits, faults in the oil and lightning strokes may cause a fire on transformers. Transformer fires are rare but the impact is great. Even though a transformer involved in a fire likely will be destroyed almost immediately, as seen in …
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An Introduction to Submarine Cables & Subsea Power Cables Introduction to Submarine Cables The development of offshore wind farms and oil and gas offshore platforms requires the installation of power, control and monitoring and communications cables between the platforms and the main land. For this purpose submarine cables are installed, which are also used for power and/or communications between islands …
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A Full Guide about Corona Effect – Corona Discharge in Transmission Lines What is Corona or Corona Discharge? When an alternating potential difference is applied across two conductors whose spacing is large as compared to their diameters, there is no apparent change in the condition of atmospheric air surrounding the wires if the applied voltage is low. However, when the …
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Design of Earthing / Grounding System in a Substation Grid By: Manuel Bolotinha Introduction to Substation Earthing Grid In high and medium voltage[1]Air Insulated Substations (AIS) the electromagnetic field, which causes are the static charges of bare cable and conductors and by the atmospheric conditions (surges), induce voltages at no-live parts of the installation that create potential differences between metallic …
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What are Harmonics and How to Filter and Eliminate it. (Manuel Bolotinha) Introduction to Harmonics The quality of electrical power supply is an important issue both for utility companies and users, but that quality may affected by electromagnetic disturbances. Among these disturbances it must be highlighted harmonics that happens in all voltage levels and whose study, calculation of acceptable values …
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Short Circuit Currents And Symmetrical Components (Manuel Bolotinha) Short Circuit Faults and Currents Short-circuits can occur phase-to-phase and phase-to-earth, mainly due to: Dielectric breakdown of insulating materials (ageing, severe overheating and overvoltages, mechanical stress and chemical corrosion are the main factors for dielectric breakdown) Decrease of creepage distance (the shortest path between two conductive parts – or between a conductive …
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