Measurement of the harmonic distortion present in a signal
The total harmonic distortion (THD or THDi) is a measurement of the harmonic distortion present in a signal and is defined as the ratio of the sum of the powers of all harmonic components to the power of the fundamental frequency. Distortion factor, a closely related term, is sometimes used as a synonym.
In audio systems, lower distortion means the components in a loudspeaker, amplifier or microphone or other equipment produce a more accurate reproduction of an audio recording.
In radio communications, devices with lower THD tend to produce less unintentional interference with other electronic devices. Since harmonic distortion can potentially widen the frequency spectrum of the output emissions from a device by adding signals at multiples of the input frequency, devices with high THD are less suitable in applications such as spectrum sharing and spectrum sensing.[1]
In power systems, lower THD implies lower peak currents, less heating, lower electromagnetic emissions, and less core loss in motors.[2] IEEE std 519-2014 covers the recommended practice and requirements for harmonic control in electric power systems.[3]
^"Analytic Method for the Computation of the Total Harmonic Distortion by the Cauchy Method of Residues".
^"Total Harmonic Distortion and Effects in Electrical Power Systems – Associated Power Technologies" (PDF).
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totalharmonicdistortion analyzer calculates the totalharmonic content of a sinewave with some distortion, expressed as totalharmonicdistortion (THD)...
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input voltage waveform using a PLL loop. Thus we can reduce the totalharmonicdistortion (THD). "Three Phase Sinosoidal PWM based Rectifier". www.mathworks...
wide variety of parameters, including level, gain, noise, harmonic and intermodulation distortion, frequency response, relative phase of signals, interchannel...
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the standard methods of measuring distortion –whether totalharmonicdistortion, conventional weighted distortion factor or the standard form of intermodulation...
percentage of "totalharmonicdistortion of the current" (THDI). Classic UPS rectifiers have a THDI level of around 25%–30%. To reduce voltage distortion, this...
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circuit. Harmonicdistortion is equivalent to adding harmonics to a signal. When a purely sinusoidal signal is in this way, a series of harmonics is superimposed...
is capable of 100 watts of output with 2.5% totalharmonicdistortion or up to about 50W at low distortion in hi-fi applications. The transmitting tubes...
as harmonics. The relative contribution of harmonics to the distortion of the ideal waveform is called totalharmonicdistortion (THD). Low harmonic content...
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noise currents into the signal ground. The 5532 attains lowest totalharmonicdistortion (THD) in an inverting (shunt-feedback) configuration with moderate...
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