Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

bundled services
utility services which are sold together, like power transmission and distribution services in non-deregulated electric utilities.
coupled line filter
a type of microstrip or stripline filter that is composed of parallel transmission lines. Bandwidth is controlled by adjusting the transmission line spacing. Wider bandwidths are obtained by tighter coupling. A two-port circuit is formed by terminating two of the four ports in either open or short circuits, which leaves ten possible combinations. Different combinations are used to synthesize low-pass, bandpass, all pass, and all stop frequency responses.
coupled lines
the electromagnetic field of two unshielded transmission lines in proximity can interact with each other to form coupled lines. Usually three conductors are needed. Examples of coupled lines are coupled microstrip lines and coupled striplines.
field controlled thyristor (FCT)
a thyristor controlled by change in the magnitude of the field current.
knowledge engineering
the process of developing an expert system.

See light emitting diode
light emitting diode (LED)
a forward-biased p-n junction that emits light through spontaneous emission by a phenomenon termed electroluminescence.
manually-controlled shunt capacitors
a bank of shunt capacitors that are controlled via SCADA signals from an operating center as opposed to local automatic control by voltage sensing.
oil-filled transformer
a transformer in which the magnetic core and the windings are submerged in an insulating oil. In addition to serving as an insulator, the oil provides a heat exchange medium to cool the transformer.
thyristor-controlled phase angle regulator
a phase shifting device used in transmission systems. The phase angle change is brought about by thyristor-based control.
thyristor-controlled series compensator
a capacitor bank installed in series with an electric power transmission line in which each capacitor is placed in parallel with a thyristor device. Each capacitor may thus be switched in or out of the line for some variable portion of the AC cycle so as to maintain the line's maximum power-carrying ability under varying load conditions.
vector controlled induction motor
a variable speed controller and motor in which the magnetizing and torque producing components of current are controlled separately. Some vector drives requires rotor position sensors. Vector controlled induction motors can operate over a wider speed range, and may produce rated torque even at zero speed, much like a DC motor. Thus, vector controlled induction motors are often used for applications that might otherwise require a DC motor drive.
voltage-controlled bus
in power-flow analysis of an electric power system, a bus at which the real power, voltage magnitude, and limits on reactive power are specified. A bus connected to a generator will be so represented.