Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

electromagnetic vulnerability (EMV)
the inability of a device, equipment, or system to perform without degradation when
subjected to electromagnetic environment of a specified power level and frequency range.
electromagnetic wave
wave in which the electric and magnetic variables are solutions of the Maxwell-Heaviside equations.
electromagnetic wave propagation
the phenomenon of electromagnetic energy propagating in the form of waves of the coupled
electric and magnetic field intensity vectors.
electromagnetically induced transparency
a technique to render optically dense media transparent by using a long-lived quantum Electromagnetic spectrum.
the study of the effect of electric charges at rest and in motion.
electromechanical relay
a protective relay that uses electrical, magnetic, and mechanical circuits to implement the operating logic.
electron band
a range or band of energies in which there is a continuum (rather than a discrete set as in, for example, the hydrogen atom) of allowed quantum mechanical states partially or fully occupied by electrons. It is the continuous nature of these states that permits them to respond almost classically to an applied electric field.
electron beam
excitation electron impact excitation due to a free electron beam rather than, for example, the conduction electrons in a gas discharge; permits high-pressure excitation without arcing.
electron beam welding
a welding process that produces coalescence of metals with the heat obtained from a concentrated beam composed primarily of high-velocity electrons impinging on the surfaces to be joined.
electron collision frequency
the average number of collisions per second an electron has with heavy particles in a medium such as plasma.
electron impact excitation
excitation of an atom or molecule resulting from collision by an electron.
electron multiplication
the phenomenon where a high-energy electron strikes a surface and causes additional electrons to be emitted from the surface. Energy from the incident electron transfers to the other electrons to cause this. The result is electron gain proportional to the incident electron energy.
electron oscillator model
simplified classical model for an atomic or molecular medium in which the charges are assumed to be bound together by springs rather than quantum mechanical potentials; provides good qualitative explanation for absorption and dispersion.
electron plasma
a plasma medium in which electrons are the mobile charge carriers and the ions form the stationary compensating positive charge background.
electron wave
the wave described by Bloch function solutions to the problem of an electron in a periodic lattice of ions.
electron-beam lithography
refers to a lithographic (or photographic) process in which the exposure energy is provided by the energy carried by a beam of focused electrons rather than by photons (light).
electronic bottleneck
the factor limiting the speed and capacity of a fiber optic communication network is ultimately the link between photons of light and the electronics required to transmit or receive and process them. In order to exploit the full bandwidth capacity of a single-mode optical fiber an optical network should minimize the number of
optical to electrical conversions and instead process the signals in the optical domain.
electronic brake
a power electronic system designed to decelerate a motor. For an induction machine, the brake supplies DC current to the stator winding, producing a stationary magnetic field, negative slip, and braking torque.
electronic motor starter
starter in which solid state devices provide reduced voltage to the motor for starting, thus limiting the starting current.
electronic nonlinear response
the nonlinear optical response resulting from the motion of bound electrons. It is characterized by moderately large response and very short (several fs) response times.