Total harmonic distortion, Electrical Engineering

Assignment Help:

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.


Related Discussions:- Total harmonic distortion

Revenue loss due to loss of opportunity to serve, Revenue Loss Due to Loss ...

Revenue Loss Due to Loss of Opportunity to Serve The revenue loss because of "loss of opportunity to serve" is a extremely relevant but less visible aspect of revenue loss. Gu

Design a pulse generator, To design a VI that can also be used as a Sub VI ...

To design a VI that can also be used as a Sub VI in another VI. The title of the VI will be Pulse Generator. The output from the VI will be of the type Analogue Waveform and

Logic diagram, design and sketch an optimal circuit that takes a 4 bit num...

design and sketch an optimal circuit that takes a 4 bit number and generates an 8 bit output equal to the square of the input

Determine the largest crest factor, A quantizer has 130 quantum levels that...

A quantizer has 130 quantum levels that exactly span the extremes of a symmetrically ?uctuating message with step size δv = 0.04 V. Determine the following: (a) |f(t)|max.

Name the effects of electric current, Name the Effects of electric current ...

Name the Effects of electric current There are three Effects of electric current:- A) magnetic effect B) chemical effect C) heating effect

Compute the maximum value of the voltage induced in the coil, Q. The coil i...

Q. The coil is placed so that its axis of revolution is perpendicular to a uniform field, as shown in Figure If the flux per pole is 0.02 Wb, and the coil, consisting of 2 turns, i

Describe the working of binary comparator, Digital Systems 1. Describe ...

Digital Systems 1. Describe the working of Binary comparator (Magnitude comparator) a. Define Binary comparator b. Binary comparator working process with logical diagrams 2.

Find the diode current and voltage in given circuit, We shall demonstrate l...

We shall demonstrate load-line analysis to find the diode current and voltage, and then compute the total power output of the battery source in the circuit of Figure (a), given the

Find the total core loss, Q. Ac measurements with constant voltage amplitud...

Q. Ac measurements with constant voltage amplitude reveal that the total core loss of a certain magnetic circuit is 10 W at f = 50 Hz, and 13 Wat f = 60 Hz. Find the total core los

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