Delmar's Standard Textbook of Electricity (MindTap Course List)
6th Edition
ISBN: 9781285852706
Author: Stephen L. Herman
Publisher: Cengage Learning
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Chapter 31, Problem 14RQ
To determine
How can a DC motor be made to operate above its base speed?
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-E1 + VR1 + VR4 – E2 + VR3 = 0 -------> Loop 1 (a)
R1(I1) + R4(I1 – I2) + R3(I1) = E1 + E2 ------> Loop 1 (b)
R1(I1) + R4(I1) - R4(I2) + R3(I1) = E1 + E2 ------> Loop 1 (c)
(R1 + R3 + R4) (I1) - R4(I2) = E1 + E2 ------> Loop 1 (d)
Now that we have loop 1 equation will procced on finding the equation of I2 current loop. However, a reminder that because we are going in a clockwise direction, it goes against the direction of the current. As such we will get an equation for the matrix that will be:
E2 – VR4 – VR2 + E3 = 0 ------> Loop 2 (a)
-R4(I2 – I1) -R2(I2) = -E2 – E3 ------> Loop 2 (b)
-R4(I2) + R4(I1) - R2(I2) = -E2 – E3 -----> Loop 2 (c)
R4(I1) – (R4 + R2)(I2) = -E2 – E3 -----> Loop 2 (d)
These two equations will be implemented to the matrix formula I = inv(A) * b
R11 R12
(R1 + R3 + R4)
-R4
-R4
R4 + R2
Chapter 31 Solutions
Delmar's Standard Textbook of Electricity (MindTap Course List)
Ch. 31 - Prob. 1RQCh. 31 - Prob. 2RQCh. 31 - Prob. 3RQCh. 31 - Prob. 4RQCh. 31 - What type of motor is known as a constant-speed...Ch. 31 - What is CEMF?Ch. 31 - Prob. 7RQCh. 31 - Prob. 8RQCh. 31 - Prob. 9RQCh. 31 - What type of motor should never be operated at no...
Ch. 31 - Prob. 11RQCh. 31 - What is the most common way of changing the...Ch. 31 - Prob. 13RQCh. 31 - Prob. 14RQCh. 31 - What device is used to disconnect power to the...Ch. 31 - Prob. 16RQCh. 31 - Who was the first person to establish a...Ch. 31 - One horsepower is equal to how many W?Ch. 31 - A motor is operating a load that requires a torque...Ch. 31 - The motor in Question 19 is connected to a 250-VDC...Ch. 31 - Prob. 1PA
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