Deck 20: Single-Phase Induction Motors

Question 1

During braking, a braking resistor installed across the converter DC bus can be used to dissipate the excess energy by closing the circuit to the resistor.

Answer 1

True

Question 2

Briefly describe two ways that regenerated voltage can be used or handled.

Answer 2

Regenerated voltage can:
• be used to slow the motor
• be dissipated by a braking resistor installed across the converter DC bus
• returned to the power source

Question 3

Many manufacturing systems and robotic material handling systems use stepper motors to position controls for fast precision movement.

Answer 3

False

Question 4

In a selsyn system, the normally stationary rotors of the induction motors are interconnected so that a manual shift in the rotor position of one machine is accompanied by an electrical rotor shift in the other machine in the same direction and of the same angular displacement as the first unit.

Question 5

____________________ units are special AC motors used primarily in applications requiring remote control.

Question 6

Synchronous Servos rely on induction to supply current and therefore magnetic flux to the rotor.

Question 7

In a synchronous Servo motor, what is the concept behind using a rotor that is made of PMs?

Question 8

List two advantages of selsyn systems.

Question 9

What are the four general conditions of a motor?

Question 10

____________________ are specialized motors that create incremented steps of motion rather than a smooth unbroken rotation.

Question 11

The electronic controller of a stepper motor provides timing and sequencing of the motor, but it operates electronically to provide circuit closure.

Question 12

In a(n) ____________________ system, one rotor acts as a transmitter and the other acts as a receiver following the sender directly or following at a prescribed offset angle.

Question 13

Briefly describe the use of an encoder used for feedback of speed and position of a rotor in a Servo motor.

Question 14

____________________ are small PM motors that use lightweight armatures to provide quick start and stop operations without a lot of inertia to overcome.

Question 15

A(n) ____________________, used to track rotor movement, uses the technique of a rotating magnet that induces a sine wave into the receiver.