Starting of motor EM-II

A synchronous motor is not self-starting because __________.

• A) Its rotor is not connected to any external circuit

• B) Its rotor has no windings

• C) Its rotor is not excited

• D) None of the above

In a synchronous motor, the stator is excited by __________.

• A) AC supply

• B) DC supply

• C) Both AC and DC supply

• D) None of the above

The starting torque of a synchronous motor is __________.

• A) Zero

• B) Low

• C) High

• D) Very high

The armature winding of a synchronous motor is placed on __________.

• A) The rotor

• B) The stator

• C) Both rotor and stator

• D) None of the above

The speed of a synchronous motor can be changed by __________. A) Changing the supply frequency B) Changing the number of poles C) Using a variable frequency drive D) All of the above

• A) Changing the supply frequency

• B) Changing the number of poles

• C) Using a variable frequency drive

• D) All of the above

The most common method of starting a synchronous motor is by __________.

• A) Direct on-line starting

• B) Star-delta starting

• C) Synchronous motor starting using DC motor

• D) Soft starting

In the DC motor starting method of a synchronous motor, the DC motor is coupled to the __________.

• A) Rotor of the synchronous motor

• B) Stator of the synchronous motor

• C) Rotor and stator of the synchronous motor

• D) None of the above

The DC motor used for synchronous motor starting is generally a __________.

• A) Series motor

• B) Shunt motor

• C) Compound motor

• D) None of the above

The DC motor is disconnected from the synchronous motor once the synchronous motor has reached __________.

• A) Full load speed

• B) Full load torque

• C) Full load current

• D) None of the above

The direction of rotation of the synchronous motor can be changed by __________.

• A) Reversing the supply voltage

• B) Interchanging any two supply phase connections

• C) Changing the DC motor direction of rotation

• D) None of the above