Question

Electric traction uses a power supply of:

• A. 25 kV, AC, 50Hz
• B. 25 kV, DC
• C. 50 kV, AC, 50Hz
• D. 50 kV, DC

Hint:

Most modern railway traction systems use single-phase 25 kV AC at 50 Hz, ensuring efficient transmission and reduced power losses.

Answer 1

The Correct Option is A

Step 1: Electric Traction Power System Electric railway traction systems predominantly use single-phase 25 kV AC at 50 Hz, which is the global standard for high-speed and mainline railways. 
Step 2: Why 25 kV AC? 
- High Voltage (25 kV) Benefits: Reduces current and minimizes power losses.
- AC vs. DC: AC systems allow for efficient power transmission over long distances.
- 50Hz Frequency: Compatible with most power grids worldwide. 
Step 3: Evaluating options: 
- (A) Correct: 25 kV AC at 50 Hz is the standard for electric traction.
- (B) Incorrect: DC traction is used in older urban metro systems, but high-speed rail uses AC.
- (C) Incorrect: 50 kV is not a standard traction voltage.
- (D) Incorrect: 50 kV DC is not used in railway traction.