Which is the main application of synchronous motor?
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 of the following is the characteristic of synchronous machine?
Synchronous Machine :
An AC system has some advantages over a DC system. Therefore, the AC system is exclusively used for the generation, transmission, and distribution of electric power. The machine which converts mechanical power into AC electrical power is called a Synchronous Generator or Alternator.
What are the physical characteristics of synchronous machine?
Synchronous motors have the following characteristics: • A three-phase stator similar to that of an induction motor. Medium voltage stators are often used. source of direct current (DC). Both brush-type and brushless exciters are used to supply the DC field current to the rotor.
What is the 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.
What is the advantage of synchronous motor?
The advantages of the synchronous motor are the ease with which the power factor can be controlled and the constant rotational speed of the machine, irrespective of the applied load. Synchronous motors, however, are generally more expensive and a d.c. supply is a necessary feature of the rotor excitation.
What are the types of synchronous motor?
This type of synchronous motor is divided into three categories and is available in three designs, each of which has unique features: Hysteresis Synchronous Motors. Reluctance Synchronous Motors. Permanent Magnet Synchronous Motors.
What is the characteristic of synchronous?
Characteristics of Synchronous Motor are constant speed motors. The speed of the motor is decided by the number of poles and frequency. Compared to an induction motor, it is very sensitive to sudden changes of load. This causes a hunting of the rotor and finally leads to stability problems.
What are the open circuit characteristics of synchronous motor?
Open-circuit characteristic (OCC) of a generator
Initially OCC follows a straight-line relation with the field current as long as the magnetic circuit of the synchronous generator does not saturate. This straight line is appropriately called the air-gap line.
What is torque speed characteristics of synchronous generator?
Power will be constant in this region and the torque of the motor is variable. Hence, it is called a constant power variable torque drive. Therefore, the speed will be more than synchronous speed. Voltage is kept constant as it can’t be varied greater than the rated voltage, only frequency is varied.
What is synchronous motor and asynchronous motor?
The synchronous motor is a type of AC motor that runs at synchronous speed. The asynchronous motor is a type of AC motor that runs on speed less than the synchronous speed. It operates on the principle of magnetic interlocking between rotor and stator field.
Why DC supply is used in synchronous motor?
for a synchronous motor we give balanced 3 phase supply to the stator which produces a rotating magnetic field.in order to produce torque we need another magnetic field which has to be relatively stationary with respect to the main field. this feild is produced on rotor winding by energising it with dc.
What is the working principle of stepper motor?
The stepper motor working principle is Electro-Magnetism. It includes a rotor which is made with a permanent magnet whereas a stator is with electromagnets. Once the supply is provided to the winding of the stator then the magnetic field will be developed within the stator.
How does synchronous motor improve power factor?
A Synchronous Motor can be made to operate at unity and leading power factor by just increasing its excitation voltage i.e. by increasing the field current. This advantage of Synchronous Motor is used to improve the power factor.