Q5. (a) Give five names of different traditional speed-control methods of induction motor. (b) For an...

Q5. (a) Give five names of different traditional speed-control methods of induction motor.

(b) For an induction motor, derive the operating condition that would provide efficient speed control over a wide range?

(c) What is the concept of “constant volts per hertz (Va/a) control” of induction motor speed control? [5+5+5=15 Points]

Expert Solution

Induction Motor Speed Control From Stator Side

1. By Changing The Applied Voltage

2. By Changing The Applied Frequency

3. Constant V/F Control Of Induction Motor

4. Changing The Number Of Stator Poles

Speed Control From Rotor Side:

1. Rotor Rheostat Control

2. Cascade Operation

3. By Injecting EMF In Rotor Circuit

(c) The speed of an induction motor can be easily controlled by varying the frequency of the 3-phase supply; however, to maintain a constant (rated) flux density, the applied voltage must also be changed in the same proportion as the frequency (as dictated by Faraday’s law).This speed control method is known as Volts per Hz. Above rated speed, the applied voltage is usually kept constant at rated value; this operation is referred to as constant HP. At low frequencies (i.e. speeds), the voltage must be boosted in order to compensate for the effects of the stator resistance.

sorry for part (b)

Manojponduru answered 3 years ago

a. For an induction motor, differentiate between synchronous speed, rotor speed and slip speed. b. State...

a. For an induction motor, differentiate between synchronous speed, rotor speed and slip speed. b. State the two basic types of construction used for the rotors of induction motors. Which is the most rugged and explain why. c. Draw full equivalent circuit for one phase of an induction motor with all parameters labelled and named. d. Draw and explain power flow diagram of 3 phase induction motor. e. Mention four (4) components of induction machine. Explain briefly the function of...

An article compared five different teaching methods for a particular course. The five methods were traditional...

An article compared five different teaching methods for a particular course. The five methods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures, computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam. We are interested in finding out if the average test scores are different for the different teaching methods. Which of the following is the appropriate set of hypotheses? Select...

Compare the brushed motor (DC motor) and a brushless motor (Induction Motor) in FIVE aspects.

There are five different types of control methods that managers can utilize to maintain control. These...

There are five different types of control methods that managers can utilize to maintain control. These are bureaucratic, concertive, objective, normative and self-control (self-management). Please compare and contrast the different types of control methods. Please describe which method you think is the most effective and which one is the least effective. Which method would you prefer to use as a manager? Does this differ from which method you would like to work under as an employee?

For full load operation of 60Hz, 380V, 4 pole 30kW induction motor, the speed is 1746rpm,...

For full load operation of 60Hz, 380V, 4 pole 30kW induction motor, the speed is 1746rpm, input current 56.2A power factor 90%. In no load operation, input current 17.3A, power factor 13.5%. In full load operation, assume that the mechanical loss is 25% of the total loss and no other losses. a) Iron loss load efficiency b) Find a rotor copper loss under full load c) Iron loss d) Find a fixed automatic hand under full load e) Find the...

Briefly explain the working of different types of Linear Induction Motor and its applications

A) Refer to the diagram on “Speed Control of a Shunt Wound DC Motor. Suppose the...

A) Refer to the diagram on “Speed Control of a Shunt Wound DC Motor. Suppose the no load voltage V = 90V, Ra + R1 = 4 ohms, Rsh + RF = 130 ohms, and the motor runs at a rated speed of 1000 RPM when IL = 4 amps. What is the back EMF VB in volts when the motor runs at IL = 6 amps? Note: Type a 1-decimal number, rounded off to the nearest 0.1 B) How...

please explain methods that can be used for varying the speed of induction machine (min 4...

please explain methods that can be used for varying the speed of induction machine (min 4 method)

A 6-pole and three-phase induction motor has synchronous speed of (1000) RPM. a) Find the no-load...

A 6-pole and three-phase induction motor has synchronous speed of (1000) RPM. a) Find the no-load and full-load operating speed of motor for the cases given, 1. 2.5Hz electrical frequency of rotor for no-load condition. 2. 6.3Hz electrical frequency of rotor for full-load condition. b) Find the speed regulation of motor by using parameters found above. c) Determine the electrical frequency of rotor under full-load condition so that speed regulation would be equal to 5%? (Electrical frequency of rotor for...

The full load speed of a three-phase four-pole 50Hz, 160kW induction motor is 1,475rpm. The starting...

The full load speed of a three-phase four-pole 50Hz, 160kW induction motor is 1,475rpm. The starting torque is 170%, the yield torque is 280% of the rated torque, and the moment of inertia of the rotor is 2.5kg-m ^ 2. The torque of the load converted to the motor shaft is 800 N-m at full load speed and the moment of inertia is 20 kg-m ^ 2. a) Find the starting time when the load torque is assumed to be...

Question