A bus cooling fan that operates without an external electrical power
supply. The fan is positioned proximate two bus bars of a polyphase
electrical system. The fan includes a rotor supporting fan blades and
mounted on an axle. The axle is supported by cross-braces in a shroud
surrounding the rotor. The shroud is open at the ends. The fan is
fabricated of non-ferrous, non-conducting material with the exception of
the rotor. The bent rods which interact with the electromagnetic field
created by the current-carrying bus bars of the polyphase electrical
system to make the rotor function as an induction motor when the fan is
placed proximate two bus bars.
