Transformer - 1 Video Lecture | Electrical Machines for Electrical Engg. - Electrical Engineering (EE)

Ans. A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. It consists of two or more coils of wire, known as windings, which are magnetically coupled but electrically isolated. The primary winding receives electrical energy from a source, while the secondary winding delivers the transformed energy to the load. The transformer works on the principle of Faraday's law of electromagnetic induction, where a changing magnetic field induces a voltage in a coil.

Ans. The main components of a transformer are: - Core: It provides a path for the magnetic flux and is usually made of laminated iron or steel to minimize eddy current losses. - Windings: The primary and secondary windings are coils of wire wound around the core. The number of turns in each winding determines the voltage transformation ratio. - Insulation: It separates the windings and prevents electrical breakdown between them. - Tap changer: It allows adjusting the turns ratio to compensate for voltage fluctuations. - Cooling system: Transformers may have cooling systems such as oil or air to dissipate heat generated during operation.

Ans. There are several types of transformers used in electrical engineering: - Power Transformers: They are used for high voltage transmission and distribution systems. - Distribution Transformers: They provide voltage transformation for the distribution network and are found on utility poles or in substations. - Instrument Transformers: These transformers are used for measuring current (current transformers) and voltage (voltage transformers) in power systems. - Auto Transformers: They have a single winding with a tap that allows for multiple voltage ratios. - Isolation Transformers: They electrically isolate the primary and secondary windings, providing safety and reducing noise interference. - Step-up and Step-down Transformers: Step-up transformers increase voltage levels, while step-down transformers decrease voltage levels.

Ans. The advantages of using a transformer include: - Voltage Transformation: Transformers allow for efficient voltage transformation, enabling the transmission of electrical energy over long distances. - Electrical Isolation: Transformers provide electrical isolation between the primary and secondary circuits, preventing direct contact and enhancing safety. - Power Distribution: Transformers facilitate the distribution of electrical power to various locations, minimizing energy losses. - Efficiency: Transformers have high efficiency, with minimal power losses during operation. - Adaptability: Transformers can be designed for specific voltage requirements, making them adaptable to various applications.

Ans. Transformers can be protected from faults and overload through various measures: - Overcurrent Protection: Fuses or circuit breakers are used to protect transformers from excessive currents that can cause damage. - Buchholz Relay: It is a gas and oil-operated relay that detects faults such as internal arcing or oil leaks and initiates a trip signal to isolate the transformer. - Temperature Monitoring: Transformers have temperature sensors that detect abnormal heat levels, triggering alarms or protective actions. - Differential Protection: It compares the currents entering and leaving the transformer to detect internal faults and initiate tripping if there is a significant imbalance. - Winding Temperature Indicators: These indicators measure the temperature of transformer windings and provide early warning of potential faults or overloads.