Dictionary of Electrical Engineering
Commonly used terms in the Electrical industry.

halfpower point

The twosided halfpower bandwidth is twice the halfpower point.

halfwave rectifier

a device that passes positive polarity portions of a signal and blocks negative polarity portions of an AC signal. Ideally, for a sinusoidal input vi.t) = Vm cos.!t/, the output equals the input while the input is positive and is zero while the input is negative.

halfwave voltage

the voltage required to produce an amount of refractive index change in a medium that will retard the phase of a traversing optical wave.

harmonic analysis

the branch of mathematics dealing with the decomposition of signal functions as a linear combination of basis functions which represent "waves" of various frequencies.
When the basis functions are sines and cosines each with a frequency that is an integer multiple of the signalÃ¢â‚¬â„¢s frequency, we have trigonometric harmonic analysis, in other words classical Fourier analysis, which provides the amplitudes and phases of the constituent sinusoids.

harmonic component

a Fourier component of order greater than one of a periodic waveform.

harmonic content

the internally generated, harmonically related spectral output from a device or circuit. Harmonic energy is that energy that is at exact multiples of the fundamental frequency, generated by the nonlinearities within the device or circuit acting on the fundamental frequency.

harmonic distortion

caused by the nonlinear transfer characteristics of a device or circuit. When a sinusoidal signal of a single frequency (the fundamental frequency) is applied at the input of a nonlinear circuit, the output contains frequency components that are integer multiples of the fundamental frequency (harmonics). The resulting distortion is called harmonic distortion.

harmonic frequency

integral multiples of fundamental frequency. For example, for a 60Hz supply, the harmonic frequencies are 120, 180, 240, 300, ....

harmonic loadpull measurement

a measurement method where transfer characteristics of a device at the fundamental
frequency can be measured by electrically changing the load impedance at harmonic frequencies.

harmonic sinusoidal

component of a periodic waveform that has a frequency equal to an integer multiple of the basic frequency (or fundamental frequency). Thus the third harmonic of a power system voltage in the U.S. has a frequency of 3 x 60, or 180 Hz. For electric systems powered by sinusoidal sources, harmonics are introduced by nonlinear devices such as saturated iron cores and power electronic devices.