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A transformer transfers electrical power from one circuit to another without changing the supply frequency, i.e. it only step-up or step-down the level of voltage and current, whereas induction motor converts electrical power into mechanical power.
What is similarity between induction motor and transformer?
The Induction motor is similar as a Transformer with a rotating short-circuited secondary. The stator winding in induction motor corresponds to the primary winding in the transformer and the rotor winding in induction motor corresponds to the secondary winding in the transformer.
Why is transformer used in induction motor?
Since the rotor is short-circuited there will be a circulation of currents in the rotor, thereby transferring the energy by mutual induction. This is the main reason for an induction motor to be referred to as a transformer.
Can we use induction motor as transformer?
An induction motor is a well-known device which works on the principle of transformer. That is, when an EMF is supplied to its stator, then as a result of electromagnetic induction, a voltage is induced in its rotor. So an induction motor is said to be a transformer with rotating secondary.
In what way s 3 phase induction motor differs from that of a transformer?
(i) The induction motor has an air gap, but the transformer has a core. Therefore, the magnetizing current in an induction motor is much larger than that of the transformer. For example, in induction motor is about 30-50 % of rated current whereas it is only 1-5% of rated current in a transformer.
What are types of induction motor?
Types of Induction Motors Split Phase Induction Motor. Capacitor Start Induction Motor. Capacitor Start and Capacitor Run Induction Motor. Shaded Pole Induction Motor.
What is the working principle of induction motor?
Working Principle of Induction Motor The motor which works on the principle of electromagnetic induction is known as the induction motor. The electromagnetic induction is the phenomenon in which the electromotive force induces across the electrical conductor when it is placed in a rotating magnetic field.
Is transformer a motor?
A transformer is an alternating flux machine while induction motor is a rotating flux machine. In a transformer, mostly a ferromagnetic iron core is used as a medium for the passage of flux from primary to secondary, whereas in an induction motor, the air gap is used between rotor and stator.
What is the difference between synchronous motor and induction motor?
Synchronous motors require an additional DC power source for energizing rotor winding. Induction motors do not require any additional power source. Synchronous motors require additional starting mechanism to initially rotate the rotor near to the synchronous speed. No starting mechanism is required in induction motors.
What are the types of losses in transformer?
Types of Losses in a Transformer Iron Losses. Hysteresis Loss. Eddy Current Loss. Copper Loss Or Ohmic Loss. Stray Loss. Dielectric Loss.
What is no load test of induction motor?
The no-load test approximates the stator circuit (Rs and Xs1) and magnetization branch parameters(Xm) of an induction machine. The machine is brought to its rated speed by applying rated three phase volt- age at the stator (Vnl). Corresponding no-load current (Inl) and no-load real power input(Pnl) are recorded.
What is the efficiency of induction motor?
Efficiency of three-phase induction motors can vary from 85% to 96%. See the chart below for torque vs. slip. Induction motors of 50-100 HP for industrial applications vary in weight from 700 to almost 1,000 lbs.
What is slip in induction motor?
“Slip” in an AC induction motor is defined as: As the speed of the rotor drops below the stator speed, or synchronous speed, the rotation rate of the magnetic field in the rotor increases, inducing more current in the rotor’s windings and creating more torque. Slip is required to produce torque.
What is the emf equation of a transformer?
Therefore, RMS value of emf per turn = 1.11 x 4f Φm = 4.44f Φm. This is called the emf equation of transformer, which shows, emf / number of turns is same for both primary and secondary winding. For an ideal transformer on no load, E1 = V1 and E2 = V2 .
Why the exciting current of induction motor is so high as compared to the power transformer?
Unlike that of a power transformer, the magnetic circuit of the induction motor has an air-gap. Therefore, the exciting current of induction motor (3O to 4O% of full-load current) is much higher than that of the power transformer. Consequently, the exact equivalent circuit must be used for accurate results.
Which motor is similar to that of a transformer Why?
The principle of an induction motor is similar to that of a transformer. The main difference is that the secondary of an induction machine is rotating and the secondary of a transformer is fixed.
What are the 2 types of induction motor?
Single-phase induction motors and three-phase induction motors are the two main types of induction motors.
What are the two main types of induction motor?
Induction motors are classified into two types namely single phase induction motor and three-phase induction motor. As their name suggests, a 1-phase induction motor is connected to a single-phase AC power supply whereas the 3-phase induction motor can be connected to a three-phase AC power supply.
What are the main parts of induction motor?
Parts of Induction Motors Stator. The stator is the stationary portion of the motor and delivers a rotating magnetic field to interact with the rotor. Rotor. The rotor is the central component of the motor, and is fixed to the shaft. Shaft. The motor shaft is fixed within the rotor, and rotates with it. Bearings. Casing.
What are the starting methods of induction motor?
Methods of Starting Three Phase Induction Motors. Direct-on-Line Starter (DOL) Star Delta starter. Auto-Transformer Starting. Rotor Resistance Starter. Review.
Can induction motor run at synchronous speed?
So, theoretically, the Induction motor can never run at synchronous speed. But due to the reduction of speed, again lag influx will be achieved, and the motor will continue to move at this speed due to flux difference between rotor and stator. In short, an induction motor cannot run at induction speed.
What are the applications of induction motor?
These are the most common type of AC motor and are important to industry due to their load capacity, with Single-Phase induction motors being used mainly for smaller loads, for example in household appliances whereas, Three-Phase induction motors are used more in industrial applications including compressors, pumps, May 5, 2016.
