What is meant by bundle conductor?

For the transmission of high voltage two or more conductors are used per phase, these conductors are called bundled conductors. They perform better than single conductor by reducing the corona effect. A single large conductor may have more skin effect then the smaller conductor hence bundled conductor perform better. The bundled conductors have high GMR and hence the reactance and inductance of the line decreases. The bundled conductors have more charging current value than the single conductor and hence helps improving power factor.  Additionally the lines produce heat as current is passed through them, and with increased temperature of conductor more resistance is faced by the current. Bundled conductor have more surface area in contact with air and therefore has a ability to cool down faster than single conductor.

More than one conductor within close proximity per phase is bundle conductor. it is used for high voltage transmission to reduce corona effect, voltage gradient.

Bundle conductor consist of three or four conductor for each phase .the conductor are separated by means of spacer at regular intervals .bundle conductor are primarily employed to reduce the corona loss &radio interference also improve the efficiency.

Mostly long distance power lines are either 220 kV or 400 kV, avoidance of the occurrence of corona is desirable. The high voltage surface gradient is reduced considerably by having two or more conductors per phase in close proximity. This is called Conductor bundling

it is a group of bare wires fastened together inside the insulation in helical shape the purpose  of this shaping is making the cable or the insulated wire flexible and able to be bent , also to increase the conductivity as electrons flow on the outer surface of the conductor .

Bundle conductor means the cable is twisted between phases and hold by tape/armour/any kind that can hold the twisted cable.