Design of Electrical Machines Mock Test 10

10%

Question 1 of 10

1. What is the assumption made in the calculation of the specific permeance?

mmf is kept constant

current is kept constant

voltage is kept constant

speed is kept constant

Question 1 of 10

Question 2 of 10

2. Which machine incorporates the usage of the closed slots?

induction motors

synchronous motors

dc motors

special motors

Question 2 of 10

Question 3 of 10

3. How is the flux distributed in the field form?

to reduce the high current

to reduce the high voltage

to reduce the harmonics

to keep the total reluctance low

Question 3 of 10

Question 4 of 10

4. What series is used to analyze the field form?

z-transform

fourier series

fourier transform

z-series

Question 4 of 10

Question 5 of 10

5. What is the formula for the zigzag permeance?

zigzag permeance = 1/average width of the rotor tooth *(1/2 * mmf per slot²)

zigzag permeance = average width of the rotor tooth *(1/2 / mmf per slot²)

zigzag permeance = average width of the rotor tooth * (1/2 * mmf per slot²)

zigzag permeance = average width of the rotor tooth / (1/2 * mmf per slot²)

Question 5 of 10

Question 6 of 10

6. How many factors are used to determine the specific magnetic loading?

Question 6 of 10

Question 7 of 10

7. What is the formula of the permeance of the strip in the conductor portion?

permeance of the strip = permeability in air * area of the flux path * length of flux path

permeance of the strip = permeability in air * area of the flux path / length of flux path

permeance of the strip =1 / permeability in air * area of the flux path * length of flux path

permeance of the strip = permeability in air / area of the flux path * length of flux path

Question 7 of 10

Question 8 of 10

8. The fractional horsepower motors have efficiency of order of 98%.

true

false

Question 8 of 10

Question 9 of 10

9. What is the formula of the zigzag specific permeance?

zigzag specific permeance = average width of the rotor tooth / length * (1/2 * mmf per slot²)

zigzag specific permeance = average width of the rotor tooth * length / (1/2 * mmf per slot²)

zigzag specific permeance =1/ average width of the rotor tooth * length * (1/2 * mmf per slot²)

zigzag specific permeance = average width of the rotor tooth * length * (1/2 * mmf per slot²)

Question 9 of 10

Question 10 of 10

10. How should the air gaps be present in the magnetic circuit according to length and cross section?

high length, high cross section

low length, low cross section

low length, high cross section

high length, low cross section

Question 10 of 10