Which of the following DC motors has almost constant speed over their full load range?
A. Series.
B. Shunt.
C. Compound (cummolative).
D. none of these.
Show Answer
Answer: B
Share your understanding of this question with the correct explanation.
The DC motor that has almost constant speed over its full load range is the Shunt motor.
Shunt motors are designed to have good speed regulation, meaning that they can maintain a relatively constant speed regardless of the load applied to them. The speed regulation of a motor refers to its ability to maintain a consistent speed despite variations in the load torque.
In a shunt motor, the field winding is connected in parallel (shunt) with the armature winding. This configuration allows the shunt motor to maintain a nearly constant speed across the full load range.
When the load on a shunt motor increases, the armature current increases to provide the necessary torque. However, the shunt field current remains relatively constant, allowing the motor to maintain its speed.
On the other hand, series motors and compound motors (both cumulative and differential) have poorer speed regulation. The speed of series and compound motors can vary significantly with changes in the load, making them less suitable for applications that require constant speed.
Therefore, the correct answer is B: Shunt. A shunt motor has almost constant speed over its full load range, making it the best choice among the options given.