Dc machine dynamic performance, Electrical Engineering

Assignment Help:

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.


Related Discussions:- Dc machine dynamic performance

Explain virtual memory, Explain virtual memory. The term virtual memor...

Explain virtual memory. The term virtual memory considers as to something that appears to be present but in fact it is not. The virtual memory technique permits users to use m

Calculate the amplitude and the frequency of the sine wave, (a) The key el...

(a) The key elements of a protocol are the syntax, semantics and timing. Give a brief explanation of each of these key elements. (b) A file contains 4 million bytes. Compare

How you can convert a galvanometer to a voltmeter, To convert a galvanomete...

To convert a galvanometer to a voltmeter, you should add a: a) High resistance in series b) High resistance in parallel c) Low resistance in series d) Low resis

The a.c/d.c. generator - electromagnetic torque, Note, the armature curren...

Note, the armature current is produced in pulses as the armature rotates under the poles, so the torque also pulsates. This can give rise to extra wear on bearings and the engin

Describe 74ls139 memory decoder, Describe 74LS139 memory decoder. The 7...

Describe 74LS139 memory decoder. The 74LS139 is a dual 2-to-4 line decoder. This contains two separate 2-to-4 line decoders - all with its address, output and enable connection

What the voltage gains in the fet amplifier, Q. What the voltage gains in t...

Q. What the voltage gains in the FET amplifier? For common source  Voltage gain=V o /V i = - µRd / Rd + rd where µ is the amplification factor,Rd the drain resistance a

Calculate the induced voltage, Q. A four-pole, lap-wound armature has 144 s...

Q. A four-pole, lap-wound armature has 144 slots with two coil sides per slot, each coil having two turns. If the flux per pole is 20 mWb and the armature rotates at 720 r/min, cal

Regenerative braking control - motor control , Regenerative Braking Control...

Regenerative Braking Control In this  methods  motor  behaves like a  generator  and the kinetic energy of the  motor  and connected load is  returned to the supply. If means

Telecommunication, Design a low noise amplifier using an Infineon RF transi...

Design a low noise amplifier using an Infineon RF transistor BFP640. The amplifier is to be used to amplify the L2 GPS signal and so the centre frequency is 1227MHz and bandwidth 4

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd