Effect of feedback on dynamic response and bandwidth, Electrical Engineering

Assignment Help:

Q. Effect of feedback on dynamic response and bandwidth?

Let us consider the block-diagram representation of the open-loop system shown in Figure 16.2.5(a), whose direct transfer function is given by

1499_Effect of feedback on dynamic response and bandwidth.png

corresponding to which, the transient solution of the system is of the form given by

c(t) = Ae-t/τ

The transient in this system is seen to decay in accordance with a time constant of τ seconds. By placing a feedback path H around the direct transfer function, as shown in Figure (b), the closed-loop transfer function is then

2190_Effect of feedback on dynamic response and bandwidth1.jpg

2203_Effect of feedback on dynamic response and bandwidth2.png

and the corresponding transient solution of the closed-loop system is of the form

cf (t) = Afe-[(1+HK)/τ ]t

where cf(t) represents the transient response of the output variable with feedback. Comparing Equations, it is clear that the time constant with feedback is smaller by the factor 1/(1 + HK), and hence the transient decays faster.

By treating the differential operator p as the sinusoidal frequency variable jω, i.e., p = jω = j(1/τ ), it follows from Equation that the bandwidth of the open-loop system spreads over a range fromzero to a frequency of 1/τ rad/s. On the other hand, for the system with feedback, Equation reveals that the bandwidth spreads from zero to (1 + HK)/τ rad/s, showing that the bandwidth has been augmented by increasing the upper frequency limit by 1 + KH.


Related Discussions:- Effect of feedback on dynamic response and bandwidth

Induced emf, applications of dynamically induced emf

applications of dynamically induced emf

Find the current by means of mesh-current analysis, For the network shown i...

For the network shown in Figure, find the current delivered by the 10-V source and the voltage across the 3- resistor by means of mesh-current analysis.

Draw and explain the circuit of wein bridge oscillator, Q. Draw and explain...

Q. Draw and explain the circuit of Wein bridge oscillator. Obtain the expressions for the (i) frequency of oscillation and (ii) condition for oscillation. Will oscillat

Explain current-to-current amplifier, Q. Explain Current-to-Current Amplifi...

Q. Explain Current-to-Current Amplifier ? The circuit given in Figure is to amplify a current fed to the input of the op amp. Applying KCL at Y, i 1 + i S = i o S

Explain the working of leds, Q. Explain the working of LEDs OPTOELECTRO...

Q. Explain the working of LEDs OPTOELECTRONIC devices either produce light or use light in their operation. The first of these, the light-emitting diode (LED), was developed to

Show the subtraction method, Q. Show the Subtraction Method? For this p...

Q. Show the Subtraction Method? For this procedure (method), start with a weighted position value greater that the number. If the number is greater than the weighted position f

Power distribution, Power Distribution You will study about the legisl...

Power Distribution You will study about the legislative measures that have been taken by our government to address these challenges. In particular, we discuss the Energy Conse

Explain about half duplex transmission, Q. Explain about Half Duplex Transm...

Q. Explain about Half Duplex Transmission? Half Duplex Transmission A half-duplex channel can receive andsend, though not at the same instance. It's like a one-lane bridge w

The fundamental frequency , The frequency domain representation of a signal...

The frequency domain representation of a signal is shown  below: i. What are the fundamental frequency and the corresponding period of this signal (shown in Figure )? ii.  Pl

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