Question 559Electricity & Electronics - Assistant Engineer

The correct answer is C) synchronous type with wound field. In moderate to high power AC drive systems, the propulsion motor most often utilized is the synchronous type with wound field. This is because synchronous motors offer higher efficiency and better speed control capabilities compared to induction motors, which are more suitable for lower power applications. The wound field design allows for adjustable excitation, enabling precise speed and torque control, making synchronous motors the preferred choice for higher power marine propulsion systems. The other options are incorrect because: A) wound rotor induction motors are less efficient and have limited speed control; B) squirrel cage induction motors are better suited for constant speed applications; and D) split phase induction motors are typically used for low-power, single-phase applications, not the moderate to high power ranges discussed in the question.