Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Explain the term total harmonic distortion. Describes the functionary of a total harmonic distortion analyzer.
Total Harmonic Distortion: Nonlinear behaviors of circuit elements introduce harmonics in the output waveform and the resultant distortion. A nonlinear system produces harmonics of an input sine wave, the harmonics consisting of sine waves with frequencies which are multiples of the fundamental of the input signal. Total harmonic distortion is measured in terms of the harmonic content of the wave, as given by equation.
A measure of distortion represented by a particular harmonic is simply the ratio of amplitude of harmonic to that of the fundamental harmonic distortion is then represented.
Harmonic Distortion Analyzer: a harmonic distortion analyzer which is used to measure THD. The signal source has very low distortion and this can be checked by reading its output distortion by connecting directly into the analyzer. The signal from the source is fed into the amplifier under test. The generates harmonics and the original frequency (fundamental). The fundamental frequency is removed by the notch filter.
In the manual system of the switch SW is first placed imposition and the total content of fundamental and harmonics is measured. Then the switch is moved to position to measure just the harmonics. The value of THD is then fond from equation.
The meter can be calibrated by putting the switch in position and adjusting the reading for full scale deflection. Wight the switch in position the meter reading is now proportional to THD.
Shows an alternative arrangement, where the values of are read simultaneously and their ratio calculated and displayed as THD on the indicator. For good accuracy the notch filter must have excellent rejection and high pass characteristics. It should attenuate the fundamental by 100 db or more and the harmonics by less than 1dB. The filter also needs to be tuned accurately to the fundamental of the signal source. This is difficult to achieve manually and most distortion analyzer do this automatically. A common from of notch filter is Wien Bridge. The balances at one frequency only and at this frequency the output voltage at the frequency only and at this frequency the output voltage at the bridge null detector is minimum.
Switching characteristics When a positive signal is applied GTO starts conducting before initiation of conduction anode current is zero and anode to cathode voltage Va
Explain the effect of temperature on the resistivity of conducting materials. The resistance of most metals rises with rise of temperature whereas that of semiconductors and el
Whose principle or law states that each point on a wave front may be considered a new wave source? Is it: w) Snell's Law x) Huygen's Principle y) Young's Law z)
Q. Discuss the disadvantages of an RC coupled amplifier? RC coupled amplifiers have a few disadvantages. The resistors use dc power and so the amplifier has low efficiency. The
a) State the principle of working of transformer. b) A 230/110 V, single-phase transformer takes an input of 350 volt-amperes at no load while working at rated voltage. The core
Q. Illustrate about Full Duplex Transmission? Full Duplex Transmission Data can travel in both directions simultaneously. There is no need to switch from transmit to receive
(a) For a series RLC resonant circuit, find an expression for the voltage across the resistance VR and obtain the ratio V R /V S , where V S is the applied voltage. Identify the e
Q. The cutoff frequency of a dominant mode in an air-?lled rectangular waveguide is 3 GHz. What would the cutoff frequency be if the same wave - guide were ?lled with a lossless di
how to model a doubly fed induction generator inside simulink?
Q. Illustrate Core Losses in magnetic core material? Iron-core losses are usually divided into two components: hysteresis loss and eddy-current loss. The former is proportional
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd