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
how unbalanced effect in wave winding is considered to be balanced?

A keyboard shortcut for a command. For example, Ctrl + Alt + Delete are an accelerator key for the task manager in Windows 95.

i dont understand why equalizer connection is not used in wave windings?

a. Describe the memory allocation schemes in an embedded system. Also give a short-note on extended memory. (6) b. Consider a byte - addressable computer with 16 - bit addresses

Explain the working of an npn transistor. Working of npn transistor: In an npn transistor is demonstrated in the figure. The emitter base junction is forward biased whereas

Define Combinations of logic gates? The Logic gates be able to combined to produce more complex functions. They can as well be combined to substitute one kind of gate for anoth

Determine and plot for 5 keV to 100 MeV the fraction of the total cross section due to each of the four interaction processes for      (a) hydrogen,      (b) nitrogen,

Q. What are the Constructional Features of DC Machines? Adc generator ormotormay have asmany as four fieldwindings, depending on the type and size of the machine and the kind o

A 3-phase transmission line is 200km long. The line has a per phase series impedance of 0.25+j0.45 Ω/km and shunt admittance of j7.2 μS/km. The line delivers 250MVA, at 0.6 lagging

Calculate the resistance of a 2 km length of aluminium overhead power cable if the cross-sectional area of the cable is 100 mm 2 . Take the resistivity of aluminium to be 0.03x10 -