How is the direction of rotation of the main...

Question 1 / 270705eccefa4bacbc34ba4d485e4

Question 1 of 270705eccefa4bacbc34ba4d485e4

How is the direction of rotation of the main propulsion motor in a modern AC propulsion drive system reversed?

Question 1 of 27070

How is the direction of rotation of the main propulsion motor in a modern AC propulsion drive system reversed?

🔍 Key Concepts

• AC propulsion motor control vs. DC motor control • How phase sequence of a three-phase AC supply affects rotation direction • Role of field winding and armature current in DC motors, not modern AC drives

💭 Think About

• Ask yourself: In a three-phase AC motor, what actually determines the direction of the rotating magnetic field? • Which choices describe methods used mainly with DC motors (field and armature current changes) rather than modern AC propulsion drives? • Does a power directional relay normally control motor rotation, or does it serve a protective/monitoring function?

✅ Before You Answer

• Identify which options refer to three‑phase AC supply characteristics • Eliminate options that are typical of DC motor control methods • Consider the normal purpose of directional relays in power systems: control of direction or protection/indication?

Question 1 of 27070

How is the direction of rotation of the main propulsion motor in a modern AC propulsion drive system reversed?

electronically changing the phase sequence of the voltages generated by the power converter

changing the direction of current flow in the motor's field winding

reversing the direction of current flow in the armature

power directional relays

Question 1 / 270705eccefa4bacbc34ba4d485e4

Question 1 of 270705eccefa4bacbc34ba4d485e4

How is the direction of rotation of the main propulsion motor in a modern AC propulsion drive system reversed?

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Question 1 of 27070

How is the direction of rotation of the main propulsion motor in a modern AC propulsion drive system reversed?