The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

Help on dc motor question mechanical engineering

A DC servo motor mist accelerated from rest to 30 rad/sec in 3 sec. the rotating mass has a moment of inertia of 5 kgm^2. The load torque is 20NM and the friction torque is 1.2NM. The damping coefficient is 0.05Nm/s radian. The torque constant is 120Nm per ampere. Determine the required current just before the acceleration.
Can some help me to calculated
(edited 6 years ago)
image.jpgHi guys can please help me. How to work out the answer
Original post by Rashik gurung
Hi guys can please help me. How to work out the answer


I've merged your threads together as I believe they are asking the same question.

Regarding your questions, can you post your working please of what you have done so far? That way hopefully someone will be able to help you with where you are going wrong or where you need to go next.
Original post by Smack
I've merged your threads together as I believe they are asking the same question.

Regarding your questions, can you post your working please of what you have done so far? That way hopefully someone will be able to help you with where you are going wrong or where you need to go next.


To add to what Smack has said, I've calculated them just now myself and obtained the answers.

To give you a clue, start with the simple mechanical definition of power, that is:

P=ωT P = \omega T

then use the basic definition of efficiency to obtain the input current at the given voltage:

e="benefit"/"cost" e = "benefit" / "cost"

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you