24 Questions
What is the main reason for keeping the air gap as small as possible in a three-phase induction machine?
To keep the magnetizing current low
What is the purpose of the slots in the stator of a three-phase induction machine?
To accommodate the three-phase windings
What is the name of the part of the induction machine that rotates?
Rotor
What is the main advantage of using power electronic converters as a supply source for an induction machine?
To augment the characteristics of the machine
What is the primary reason for the widespread use of induction machines in industries and household applications?
They offer several advantages, including being cheap and rugged
What is the percentage of total electrical energy generated that is consumed by induction machinery?
60%
What is unique about the starting process of an induction machine?
It is self-starting
What is the characteristic of an induction machine that allows it to run at almost constant speed from no-load to full-load condition?
It is maintenance-free
What is the purpose of short-circuiting the rotor winding through external resistance?
To improve the performance of the motor
What type of machine is used for high-power applications (MW range)?
Wound rotor induction motor
What is the purpose of the three copper rings called 'slip rings' on the rotor shaft?
To connect the rotor winding to the external resistance
What is the spatial phase difference between the three-phase stator windings?
120∘
What is the principle of operation of a three-phase induction motor based on?
Faraday's law of electromagnetic induction
What is the result of supplying a balanced three-phase supply to a three-phase stator winding?
A rotating magnetic field
What is the requirement for the rotor winding in a wound rotor induction motor?
It should be short-circuited
What is the application of a wound rotor induction motor in wind energy generation?
As a generator
What are the two types of rotor structures?
Squirrel cage and slip ring
What are the slots in the stator lamination used for?
To accommodate three-phase windings
What is the advantage of using open slots in stator design?
Lower leakage reactance
What is the shape of the squirrel cage rotor?
Skewed
What is the purpose of the end rings in a squirrel cage rotor?
To short the copper or aluminum bars
What is the characteristic of the construction of a squirrel cage rotor?
Rugged and strong, requiring no maintenance
What is the similarity between a wound rotor and a stator?
Both have three-phase windings
How are the three-phase windings in a stator connected?
Either in star or in delta
Learn about induction motors, widely used in industries and households, and their applications. Understand their characteristics and importance in electrical energy consumption.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
