Transformers Questions & Answers Part-2
Auto-transformer Advantages: Auto-transformers in comparison with the double winding transformers are generally advantageous of the voltage ratio is favorable from the point of view of the equivalent size The reduction…
Transformers Questions & Answers Part-3
Insulation Materials used in Transformers and Induction Motors Insulation materials used in transformers and motors are classified based on the temperature withstand capability. Some of the insulation classes used in…
Transformers Questions & Answers Part-4
Where Star (wye) Delta transformer is used in Power system Star-Delta Transformer (Y-Δ ) Primary Y (High Voltage side) and Secondary ( Low Voltage side) Δ is generally used at…
Power System Protection and Relays Questions & Answers
What is protective relay? It is an electrical device designed to initiate the isolation of a part of the electrical installation, or to operate an alarm signal, in the event…
Why Starting Current of Induction Motor is High
Starting Current in Induction Motor: Starting current of induction motor is as high as 5 to 7 times the normal full load current. Therefore different starting of induction motor, methods…
Auto Recloser Circuit Breaker in Power System
Most of the faults on over head lines are transient in nature. About 85% to 90% of faults are momentary and caused by tree branches, lightning, birds etc. These conditions…
Current Limiting Reactors and Short Circuit Currents
A current limiting reactors is also called as series reactors. It is an inductive coil having large inductive reactance compared to the resistance and is used to limit the short…
Surge Impedance Loading of Transmission Line
Loading of any transmission line depends on, Thermal limitation (I2R limitation) Voltage regulation Stability Limitation This is defined as the load (of unity power factor) that can be delivered by…
Parallel Operation of Alternators
Requirements of parallel operation of alternators: The alternators which are to be operated in parallel should meet the following requirements so as to make the operation successful. Requirements are: Two…
Induction Motors Faults and Protection
Faults that can occur in 3 phase induction motors and associated protections are discussed below: Stator faults: These faults include phase to phase faults, earth faults, and inter turn faults.…
