Which type of single-phase motor is described as simpler and less expensive?

• A. Capacitor-start type
• B. Synchronous type
• C. Repulsion-induction type
• D. Wound-rotor induction motor

Answer: (C)

The key idea is that this type keeps starting mechanics simple by using the interaction between the stator field and a rotor followed by standard induction operation, without relying on additional starting components. It starts through a repulsion action between rotor windings and the stator field, which provides starting torque with a straightforward, compact arrangement. Once up to speed, it behaves like a regular induction motor, so there’s no need for extra starting circuitry such as capacitors or separate starting windings. That simpler hardware and fewer specialized components generally translate to lower manufacturing cost and easier maintenance compared with designs that require capacitors, switches, or complex rotor assemblies. The other motor types listed involve more elaborate starting methods or rotor configurations, making them more costly or intricate in comparison.