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Whereas a induction motor is said to rotating flux transformer because rotating flux is used to induce the mutually induced emf in the rotor of the motor In a alternating flux transformer the frequency of induced emf and current in primary and secondary is always same.
Why is transformer used in induction motor?
Induction motor is a generalized transformer. In transformer the flux produced is time alternating and not rotating. There is no air gap between primary and secondary of transformer where as there is a distinct air gap between stator and rotor of motor which gives mechanical movability to motor.
Can induction motor be used 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.
What happens if an induction motor runs above its rated voltage?
Induction and synchronous motors are designed for a specific voltage per frequency ratio (V/Hz). When motor operates at higher V/Hz than rated, the overfluxing occurs, which may cause saturation of the stator and rotor magnetic core. Saturation causes overheating and can lead to motor failure.
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 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.
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 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.
Why synchronous motors are not self starting?
Above a certain size, synchronous motors are not self-starting motors. This property is due to the inertia of the rotor; it cannot instantly follow the rotation of the magnetic field of the stator. Once the rotor nears the synchronous speed, the field winding is excited, and the motor pulls into synchronization.
Will low voltage damage a motor?
Just as higher voltages can help reduce motor operating temperatures, low voltage is a major cause of motor overheating and premature failure. A low voltage forces a motor to draw extra current to deliver the power expected of it thus overheating the motor windings.
What happens if motor runs on low voltage?
Low voltage can lead to overheating, shortened life, reduced starting ability, and reduced pull-up and pullout torque. The starting torque, pull-up torque, and pullout torque of induction motors all change, based on the applied voltage squared.
How much voltage drop does it take to cause problems to a motor?
In general, satisfactory motor performance requires a voltage within ± 5% of its rated nominal value in steady-state operation, Starting current of a motor can be 5 to 7 times its full-load value (or even higher). If an 8% voltage drop occurs at full-load current, then a drop of 40% or more will occur during start-up.
What is the working principle of transformer?
A transformer operates on the principle of electromagnetic induction. It has a magnetic core over which two sets of windings, termed as primary and secondary, are suitably placed. When one of the windings is connected to an AC supply, an emf is induced on the other winding which is proportional to the number of turns.
What are the losses in transformer?
A transformer’s output power is always slightly less than the transformer’s input power. These power losses end up as heat that must be removed from the transformer. The four main types of loss are resistive loss, eddy currents, hysteresis, and flux loss.
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 .
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.
What are the parameters of induction motor?
The motor parameters to be estimated are: stator and rotor resistances (R1 and R2), stator and rotor leakage inductances (lσ1 and lσ2), magnetizing inductance (LH), moment of inertia (J) and friction coefficient (KD). For this, we developed a function approximator algorithm using a differential evolution technique.
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 advantages of induction motor?
Advantages of an induction motor (IM): The working of an induction motor is very simple. It is very cheap in cost to compare the other motors. It is a highly efficient motor. The brushes are not used in an induction motor. The maintenance of IM is very less compared to the DC motor and synchronous motor.
What is the main disadvantage of synchronous motors?
Disadvantages or Demerits: Synchronous motors requires dc excitation which must be supplied from external sources. Synchronous motors are inherently not self starting motors and needs some arrangement for its starting and synchronizing. The cost per kW output is generally higher than that of induction motors.
How do you know if a motor is synchronous?
The speed of the rotating stator field is called the synchronous speed. The frequency of the power supply and the number of poles of the machine determine the synchronous speed. A synchronous motor is one in which the rotor turns at the same speed as the rotating magnetic field in the stator.
