ParameterValueUnitRemarksInertia36tonne m?Damping20N-m.sTrain mechanisms onlyLoad Torque117.720kN-mA train has the effective total properties in thepreceding table. It is desired to be able to completelystop the train from full speed in 15 seconds, whilemaintaining rated supply to the field.1. Find the number of DC motors needed to run anddecelerate the train without any motor being subjectedto more than its rated capabilities. Assume uniformload distribution; identical machine models, terminalvoltages, and controls.2. Derive an expression for the armature current la(t) ineach machine.3. Derive an expression for the instantaneous terminalvoltage Va(t) required for the controllers. 4. Due topractical limitations, it is often necessary to stopregenerative braking once one of the following occurs:zero-speed, zero Va(t), or zero la(t). Determine theangular speed (in rpm) at which this occurs.

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Answered: ply to the field. DC motors needed to…

Engineering

Mechanical Engineering

ply to the field. DC motors needed to run ithout any motor being sub

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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