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

Define stability - characteristics of discrete time systems, Define Stabili...

Define Stability - Characteristics of Discrete Time Systems? The LTI system is stable if its impulse response satisfies the condition This condition is satisfie

Buck converter - power supplies , Buck Converter In buck  converters th...

Buck Converter In buck  converters the output  voltage is  always  less than the  input  voltage. The basic  circuit  of buck converter is shown  in figure. The operation of th

Calculate the unknown thermal conductivity, Derive the mathematical 3-D hea...

Derive the mathematical 3-D heat conduction equation in Spherical Coordinates? A furnace is made up of three layers of thicknesses 250 mm, 150 mm nad 100 mm with thermal conduct

Test quipment, The frequency of an oscillator may be measured by an oscillo...

The frequency of an oscillator may be measured by an oscilloscope with a callbrated time base(True/False)

Why negative feedback is employed in wein bridge oscillator, Q. Why negativ...

Q. Why negative feedback is employed in Wein Bridge Oscillator. Also explain the working of oscillator? The Wein Bridge Oscillator consists of two stages of the RC coupled ampl

Rim read interrupt mask instruction, RIM Read Interrupt Mask Instruction ...

RIM Read Interrupt Mask Instruction This  instruction is used  to read the  status  of interrupts  and  read the serial  input  data. The status  byte is loaded  into  the accu

Importance of transistor, Importance: The transistor is the main activ...

Importance: The transistor is the main active component in practically all current electronics, and is considered through many to be one of the greatest inventions of the 20 t

Determine the maximum value of the average torque, Q. A two-pole rotating m...

Q. A two-pole rotating machine with a singly excited magnetic field system as its stator and a rotor (that carries no coil) has a stator-coil inductance that can be approximated by

Explain thermoplastic materials, Explain Thermoplastic materials. Ther...

Explain Thermoplastic materials. Thermoplastic materials: The properties of such plastic materials do not change considerably when they are melted and after that cooled and s

What do you mean by pinch off voltage, Q. What do you mean by Pinch off vol...

Q. What do you mean by Pinch off voltage? As the voltage Vds is increased from 0 to a few volts, the drain current will increase as  determined by Ohm's law and the plot of Id

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