Dc machine dynamic performance, Electrical Engineering

Calculate the following for a 2 hp and a 20 hp dc machine, each rated for 500 rpm. Use data from the Study Plan 1 data sheet, including "hot" armature resistance value for all calculations. Note that the value of K is proportional to the field flux, and the printed value is for rated (100%) flux. Both the load moment of inertia JL and the viscous friction coefficient B are zero unless stated otherwise.

a) Calculate the eigenvalues (real or complex) for operation at rated flux and at 50% of rated flux:

b) Calculate the dominant time constant τ of the 2 hp machine and the natural frequency ωN and damping factor ζ of the 20 hp machine (assume rated flux for both machines). Use them to determine the approximate percentage overshoot and settling time (within 2%) for the rotor speed's natural response for each machine following a step change in the armature voltage. Assume zero load inertia. Plot the transient response of the rotor speed ω (in rpm) for both machines for a step in the armature voltage from 50% to 100% rated voltage, assuming no steady-state load torque (i.e., TL=0) and an initial rotor speed corresponding to the no-load speed at 50% rated voltage. Calculate the initial and final speed values for both machines.

c) Find the value of an external series resistance for both machines that will limit the steady-state stall current (i.e., speed = 0) with rated voltage to 125% of rated current. With this resistor in the circuit, repeat the eigenvalue calculation of part a) for both machines. Assume rated field flux. Plot the migration of 20 hp machine's eigenvalues (i.e., root locus) as the additional series resistance Radd is increased from 0 to its final value.

Posted Date: 3/14/2013 3:55:07 AM | Location : United States







Related Discussions:- Dc machine dynamic performance, Assignment Help, Ask Question on Dc machine dynamic performance, Get Answer, Expert's Help, Dc machine dynamic performance Discussions

Write discussion on Dc machine dynamic performance
Your posts are moderated
Related Questions
Which clipper would you prefer between the series and the shunt clipper? Why?

Q. Read-and-write memory? Writing is the same as storing data intomemory and reading is the same as retrieving the data later. RAM is said to be volatile because its contents a

Q. Show how the conservation of power is satisfied by the circuit of Figure.


An induction motor has a starting current that is 6 times the full-load current and a per-unit full- load slip of 0.04. The machine is to be provided with an autotransformer starte

DC Motor Starting When voltage is applied to the armature of a dcmotorwith the rotor stationary, no emf is generated and the armature current is limited only by the internal ar

The dielectric constant of air is practically taken as (A) more than unity.                         (B) Unity.  (C) less than unity.                           (D) Zero.

shockely equation?

You have been given a DC motor to characterize. What three measurements are required in order to develop the torque-speed curve and the acceleration curve for the unloaded motor?

Many circuits, particularly amplifiers, use negative feedback (nfb) in order to function reliably. The nfb changes the performance of the circuit to which it is applied, in most ca