Skin Effect DefinedSkin effect in transmission lines is the phenomenon where AC current concentrates near the conductor’s surface, increasing its effective resistance.Skin effect is defined as the tendency of an AC current to distribute unevenly over the cross-section of a conductor, such that the current density is highest near the surface of the skin of the conductor and decreases exponentially towards the core. This means that the inner part of the conductor carries less current than the oute

Power System Frequency DefinitionPower system frequency is the rate of change of the phase angle of AC voltage or current, measured in hertz (Hz).Historical InfluenceThe choice of 50 Hz in India and 60 Hz in other regions is based on historical and economic factors, not technical reasons.Advantages of 60 HzA 60 Hz system has more power output and allows for smaller electrical devices but may need more cooling.Advantages of 50 HzA 50 Hz system can support longer transmission distances with lower

Double loop radial network

What is Arc Interruption Theory?Arc Interruption Theory DefinitionArc interruption theory is defined as the process of stopping electrical arcs that occur when circuit contacts open.Methods of Arc InterruptionThere are two main methods: the high resistance method, which increases resistance to zero current, and the low resistance method, which uses the natural zero point of AC current.Restriking VoltageRestriking voltage is the voltage across breaker contacts at the moment an arc is extinguished

Single loop radial network

Primary circuit diagram of a step-down substation with two main transformers

What is Mobile Substations ?Mobile Substation DefinitionA mobile substation is a portable power distribution system used for temporary or emergency power supply.ComponentsIncludes transformers, cooling systems, switchgear, metering systems, protection relaying systems, auxiliary power supplies, surge protection, and cable connections.Types of Mobile Substations Compact and modular mobile substations Skid-mounted substations Containerized substations Rail-wagon substationsBenefits Offers mobility

Electrical Substation DefinitionNowadays, the demand for electrical power is growing rapidly. To meet this demand, we need larger power generating stations, which can be hydro-electric, thermal, or atomic. These stations are built in various locations based on resource availability, often far from the areas where power is consumed.Therefore, it’s necessary to transmit power from generating stations to load centers using high-voltage networks. Power is generated at low voltages but transmitted at

Ring distribution system

Method of EarthingWe connect all the points to be earthed to the earthing grid using corrosion-resistant mild steel rods, buried at least 600 mm below ground. If these rods cross a cable trench, road, underground pipework, or rail track, they should be at least 300 mm below the barrier.We use MS rods for connecting the earth grid below ground level and MS flats above ground. The connection between different earthing points and the earthing grid is called the riser. We use MS flats for the riser