What is meant by magnetic locking?

An electromagnetic lock, magnetic lock, or maglock is a locking device that consists of an electromagnet and an armature plate. A fail-secure locking device remains locked when power is lost. Fail-safe locking devices are unlocked when de-energized. Direct pull electromagnetic locks are inherently fail-safe.

Which method is used for magnetic locking?

2. Which method is/are used to perform magnetic locking? Explanation: A sub motor is needed to make the synchronous machine run till the speed of synchronous speed and to achieve that we need additional motor.

What is the principle of operation 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 crawling in induction motor?

Detailed Solution. The crawling in the induction motor is caused by harmonics developed in motor. Crawling is the tendency of particularly squirrel cage rotor to run at speeds as low as one-seventh of their synchronous speed. This phenomenon is known as the crawling of an induction motor.

What are the magnetic field concepts applicable in a synchronous generator?

The synchronous generator works on the principle of Faraday laws of electromagnetic induction. Electromagnetic induction states that electromotive force induced in the armature coil if it is rotating in the uniform magnetic field. The EMF will also be generated if the field rotates and the conductor becomes stationary.

What is magnetic locking in induction motor?

The phenomenon of Magnetic Locking between the stator and the rotor teeth is called Cogging or Teeth Locking. Even after applying full voltage to the stator winding, the rotor of a 3 phase induction motor fails to start. This condition is known as Cogging or Magnetic locking.

What are the difficulties in starting a synchronous motor?

Slight torsional vibration causing problems in machines attached to a synchronous motor, trouble starting, cracked amortisseur windings, broken couplings and the inability to maintain synchronous speed should signify potential problems in a rotor circuit.