Which statement about the arrangement of windings in a three-phase generator is true?

Which statement about the arrangement of windings in a three-phase generator is true?

• A. The windings are connected in a straight line
• B. They produce identical voltages in time
• C. They are arranged to rotate mechanically
• D. The three windings are equally spaced around the circle at 120-degree intervals

Answer: (D)

Three-phase generation needs three voltage waveforms that rise and fall one after the other by one-third of a cycle. To achieve that, the windings are placed evenly around the stator so each is 120 electrical degrees apart. As the rotor’s magnetic field sweeps past the windings, the induced voltages reach their peaks in sequence, creating three sinusoidal voltages that are 120 degrees out of phase. This spacing also helps keep the voltages balanced and makes it easy to connect the outputs in either star or delta. The windings are typically stationary on the stator while the rotor rotates, rather than the windings themselves rotating. The other statements don’t fit because a straight-line arrangement isn’t how the windings are laid out, the voltages are not identical in time, and the windings themselves don’t rotate in most designs.

Three-phase generation needs three voltage waveforms that rise and fall one after the other by one-third of a cycle. To achieve that, the windings are placed evenly around the stator so each is 120 electrical degrees apart. As the rotor’s magnetic field sweeps past the windings, the induced voltages reach their peaks in sequence, creating three sinusoidal voltages that are 120 degrees out of phase. This spacing also helps keep the voltages balanced and makes it easy to connect the outputs in either star or delta. The windings are typically stationary on the stator while the rotor rotates, rather than the windings themselves rotating. The other statements don’t fit because a straight-line arrangement isn’t how the windings are laid out, the voltages are not identical in time, and the windings themselves don’t rotate in most designs.