Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
The specific energy consumption of a train depends on which of the following ?
Acceleration and retardation
Gradient
Distance covered
All of the above
All of the above
Specific energy consumption (SEC) is defined as the electrical energy consumed in watt-hours (Wh) per ton-kilometer (t-km) of the train. It is a function of the train's motion parameters, track profile, and operational schedule, all of which directly affect the tractive effort required.
Specific energy consumption (SEC) is defined as the electrical energy consumed in watt-hours (Wh) per ton-kilometer (t-km) of the train. It is a function of the train's motion parameters, track profile, and operational schedule, all of which directly affect the tractive effort required.
SEC=Weight(tonnes)├ЧDistance(km)TotalEnergy(Wh)тАЛ
PtractiveтАЛ=FtractiveтАЛ├Чv
The total energy required by a train includes energy for acceleration, overcoming gradient resistance, and overcoming train resistance (friction and air drag). Since these components are directly influenced by the train's acceleration, the slope of the track (gradient), and the total distance between stops, all these factors contribute significantly to the total energy consumed.
Acceleration requires higher starting current, increasing SEC.
Upward gradients require additional energy, increasing SEC; downward gradients can save energy via regenerative braking.
Higher distance between stops reduces the effect of high-energy-consumption acceleration periods on the overall average.
SEC is usually expressed in Wh/t-km.
Helps in selecting optimal motor ratings.
Enables assessment of operational efficiency.
Highly dependent on train schedule (frequent stops increase SEC).
Affected by variable track conditions.
Railway electrification planning.
Energy auditing in electric traction systems.
Specific energy consumption is the most important parameter to determine the size of the traction motor and the economy of the electric traction system.
Option A, B, and C are all individual factors that change the load on the traction motors, thus affecting energy demand.
D is correct тАФ Specific energy consumption is determined by the cumulative effect of acceleration, gradients, and distances, as these dictate the total mechanical energy required to propel the train.
In competitive exams, always check if factors like 'acceleration' and 'gradient' influence power or energy; for traction, they dictate both.