Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

a crimped-type wire connector.
that which does work or is capable of doing work. In electrical systems, it is generally a reference to electrical energy measured in kilo-watt hours.
energy band
continuous interval of energy levels that are allowed in the periodic potential field of the crystalline lattice.
energy banking
pertaining to the maintenance of a thermal unit on hot reserve.
energy compaction
in a transformation, the concentration of the input signal energy into a relatively small part of the transformed signal. A linear transform of a random vector compacts the signal energy when the energy or variance of a small number of transform coefficients is large relative to the variance of the other coefficients.
energy conservation
the conservation of energy between the input and output of a system; i.e., the energy of the output signal is equal to that of the input signal to within a constant factor. A unitary or orthogonal transform conserves energy in that the energy or magnitude of the output vector is equal to that of the input vector.
energy gap
the width of the energy interval between the top of the valence band and the bottom of the conduction band.
energy level
one of the specific values possible for the energy of an electron in an atom or molecule.
energy product
the product of the magnetic flux density, Band magnetic field intensity, H at any operating point on the normal demagnetization curve, indicating the energy delivered by the magnet. The maximum energy product is commonly used to designate varying grades of materials.
energy relaxation
time the characteristic time for energy loss to scattering processes.
entropy estimation
noiseless source coding theorem states that the bit rate can be made arbitrarily close to the entropy of the source that generated the image. Entropy estimation is the process of characterizing the source using a certain model and then finding the entropy with respect to that model. The major challenge here is to approximate the source structure as close as possible while keeping the complexity of the model and the number of parameters to a minimum.
a set of objects outside the system, a change in whose attributes affects, and is affected by, the behavior of the system.
a method used in communication systems to compensate for the channel distortion introduced during signal transmission.
equivalence theorem
an electromagnetic theorem: If the tangential magnetic and electric fields are known everywhere on some closed surface S, then these fields may be replaced with equivalent electric and magnetic surface currents, respectively. These equivalent currents will produce the same field structure exterior to S as the original fields and the null field internal to S.
equivalent circuit
a combination of electric circuit elements chosen to represent the performance of a machine or device by establishing the same relationships for voltage, current, and power.
equivalent control
an algorithm used to determine a system's dynamics when restricted to a sliding surface. The method entails combining the solution to an algebraic equation involving the time derivative of the function describing the sliding surface and the dynamical system's model. See also variable structure system and sliding mode control.
equivalent current
a theoretical current used to obtain the scattered field from a surface or discontinuity. The equivalent current is formulated to represent the actual physical currents so as to result in an equivalent scattered field.
equivalent impedance
the impedance of the windings of an electromagnetic machine reflected to one side (component) of the machine. For example, in a transformer, the equivalent impedance consists of the combined leakage reactances and resistances of the primary and secondary.
equivalent noise voltage (ENV)
a noise voltage source that is effectively in series with either the inverting or noninverting input terminal of the op amp and represents the total noise contributed by the op amp if the inputs were shorted.
equivalent reactance
the reactance of the windings of an electromagnetic machine reflected to one side (component) of the machine.
See equivalent impedance