Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

brushless rotary flux compressor
a rotating machine designed to deliver pulsed output (1 MJ in 100 µs). The stator coils are excited by an external capacitor bank. The rotor is a salient structure that compresses the flux resulting in amplification of the electric pulse, by converting the rotating kinetic energy of the rotor to electrical energy.

bulb generator
a free-standing generator contained in a streamlined, waterproof bulb-shaped enclosure and driven by a waterwheel resembling a ship's propeller on a shaft which extends from one end of the enclosure. They are used in tidal power installations.
bulk power
a term inclusive of the generation and transmission portions of the power system.

bulk substation
a substation located on a high-voltage transmission line which supplies bulk power to a non-generating utility.

the practice of paralleling several conductors per phase in an overhead transmission line for the purpose of increasing ampacity and decreasing inductive reactance.

bundle spacer
a rigid structure which is used to maintain the spacing of wires in a bundled conductor on an overhead electric power transmission line.

See bundle
bundled services
utility services which are sold together, like power transmission and distribution services in non-deregulated electric utilities.

breakage of an overhead electric power line due to heating from excess current.

a measure (e.g., megawattt-days / ton) of the amount of energy extracted from each unit of fissile material invested in a nuclear reactor.

(1) a data path connecting the different subsystems or modules within a computer system. A computer system will usually have more than one bus; each bus will be customized to fit the data transfer needs between the modules that it connects.
(2) a conducting system or supply point, usually of large capacity. May be composed of one or more conductors, which may be wires, cables, or metal bars (busbars).
(3) a node in a power system problem
(4) a heavy conductor, typically used with generating and substation equipment.
bus admittance matrix
See Y-bus
bus differential relay
a differential relay specifically designed to protect high power buses with multiple inputs.

bus impedance matrix
See Z-bus
a rigid, hollow cylindrical insulator which surrounds a conductor and which extends through a metal plate such as a the wall of a transformer tank so as to insulate the conductor from the wall.
bushing transformer
a potential transformer which is installed in a transformer bushing so as to take advantage of the insulating qualities of that bushing.

common notation for radian bandwith in radians per second.

bypass switch
a manually-operated switch used to connect load conductors when an automatic transfer switch is disconnected.

in most computers, the unit of memory addressing and the smallest quantity directly manipulated by instructions. The term "byte" is of doubtful origin, but was used in some early computers to denote any field within a word (e.g., DEC PDP-10). Since its use on the IBM "Stretch" computer (IBM 7030) and especially the IBM System/360 in the early 1960s, a byte is now generally understood to be 8 bits, although 7 bits is also a possibility.