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Synchronous motors are normally used in applications in which a constant and precise speed is required. Typical applications of these low power motors are positioning machines. They are also used in robot actuators. Synchronous motors are also used in ball mills, watches, record players, and turntables.
Which is the main application of synchronous motor answer?
Applications of Synchronous Motors A synchronous motor having no load connected to its shaft is used for power factor improvement. Owing to its characteristics to behave at any electrical power factor, it is used in power systems in situations where static capacitors are expensive.
What is the main purpose of a synchronous motor in practice?
Synchronous motors are often used in large plants to drive the central air compressor. A large synchronous motor can be used to control the power factor of the whole plant, compensating the lagging power factor of a large number of medium and small induction motors.
What are the applications of 3 phase synchronous motor?
Due to constant speed characteristics, it is used in machine tools, motor generator sets, synchronous clocks, stroboscopic devices, timing devices, belt driven reciprocating compressors, fans and blowers, centrifugal pumps, vacuum pumps, pulp grinders, textile mills, paper mills line shafts, rolling mills, cement mills.
What are the advantages of synchronous motor?
Advantage or Merits: One of the major advantage of using synchronous motor is the ability to control the power factor. An over excited synchronous motor can have leading power factor and can be operated in parallel to induction motors and other lagging power factor loads thereby improving the system power factor.
What are the main parts of synchronous motor?
The Construction of Synchronous Motors A synchronous motor is generally made up of two parts, a stator the stationary part of the machine that carries the armature winding in which the voltage is generated, and a rotor the rotating part of the machine that produces the main field flux.
What is the working principle of synchronous motor?
The principle of operation of a synchronous motor can be understood by considering the stator windings to be connected to a three-phase alternating-current supply. The effect of the stator current is to establish a magnetic field rotating at 120 f/p revolutions per minute for a frequency of f hertz and for p poles.
How does a synchronous motor start?
The motor is first started as a slip ring induction motor. The resistance is gradually cut-off as the motor gains speed. When it achieves near synchronous speed, DC excitation is given to the rotor, and it is pulled into synchronism. Then it starts rotating as a synchronous motor.
How can synchronous motor be stopped?
The methods that are employed for Braking of Synchronous Motor are: Regenerative braking while operating on a variable frequency supply. Rheostatic braking. Plugging.
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.
What are the special applications of an over excited synchronous motor?
Application. An over-excited synchronous motor has a leading power factor. This makes it useful for power-factor correction of industrial loads. Both transformers and induction motors draw lagging (magnetising) currents from the line.
Why the speed of synchronous motor is constant?
When you supply 60 Hz (or 50 Hz), the motor will spin at one speed, which is dependent on the number of poles. This rotational speed will be constant with different mechanical loads, up to the point that the motor (or coupling) fails, hence it is a “constant speed” motor.
What do you mean by synchronous speed?
: a definite speed for an alternating-current machine that is dependent on the frequency of the supply circuit because the rotating member passes one pair of poles for each alternation of the alternating current.
What is the main difference between induction motor and synchronous motor?
Key differences between Induction Motor and Synchronous Motor SYNCHRONOUS MOTOR INDUCTION MOTOR The motor always runs at synchronous speed. The motor always runs at a speed less than synchronous speed. It works on the principle of magnetic locking. It works on the principle of electromagnetic induction.
What are the disadvantages of synchronous learning?
Main disadvantages of synchronous learning: Both the student and the instructor have to adhere to time schedules. Much of the training depends on the quality of the instructor. Students may not receive individual attention if other students are also in need. The learning pace is set by the instructor, not the students.
What are the benefits of a permanently excited synchronous motor?
The advantage of using synchronous motor is the ability to control the power factor. An over excited synchronous-motor has leading power factor and is operated in parallel to induction motors thereby improving the system power factor. Speed remains constant irrespective of the loads in synchronous motors.
What is the principle of synchronous generator?
The principle of operation of synchronous generator is electromagnetic induction. If there exits a relative motion between the flux and conductors, then an emf is induced in the conductors.
What are the two types of synchronous generators?
Types of synchronous machines Hydrogenerators : The generators which are driven by hydraulic turbines are called hydrogenerators. These are run at lower speeds less than 1000 rpm. Turbogenerators: These are the generators driven by steam turbines. Engine driven Generators: These are driven by IC engines.
What is difference between synchronous and asynchronous motor?
Synchronous motor is a machine whose rotor speed and the speed of the stator magnetic field is equal. Asynchronous motor is a machine whose rotor rotates at the speed less than the synchronous speed. AC Induction Motor is known as the Asynchronous Motor. Synchronous motor does not have slip.
What is the principle of a motor?
The principle of an electric motor is based on the current carrying conductor which produces magnetic field around it. A current carrying conductor is placed perpendicular to the magnetic field so that it experiences a force.
What is synchronous motor speed?
The synchronous speed is the speed of the revolution of the magnetic field in the stator winding of the motor. It is the speed at which the electromotive force is produced by the alternating machine. A machine that runs at synchronous speed is called a synchronous machine.
