Which DC motor is known for good speed regulation?

Which DC motor is known for good speed regulation?

• A. Low efficiency
• B. Good speed regulation
• C. High starting torque
• D. Poor speed regulation

Answer: (B)

Speed regulation is how much the motor’s speed changes when the load changes. A DC shunt-wound motor has its field winding connected across the supply, so the magnetic field remains nearly constant even as the armature current changes to provide torque. With the field strength steady, the speed for a given armature voltage stays fairly constant despite load variations, which means it has good speed regulation. In contrast, a series-wound motor’s field strength increases with current, causing larger speed swings as the load changes, so its regulation is poor. Compound motors can blend characteristics, but the clean, steady speed under varying load is a hallmark of the shunt-wound DC motor.

Speed regulation is how much the motor’s speed changes when the load changes. A DC shunt-wound motor has its field winding connected across the supply, so the magnetic field remains nearly constant even as the armature current changes to provide torque. With the field strength steady, the speed for a given armature voltage stays fairly constant despite load variations, which means it has good speed regulation. In contrast, a series-wound motor’s field strength increases with current, causing larger speed swings as the load changes, so its regulation is poor. Compound motors can blend characteristics, but the clean, steady speed under varying load is a hallmark of the shunt-wound DC motor.