The Bulb-Type Generators of Rock Island Power Station and Their Novel Cooling System

Presentation of a new cooling system for bulb type generators, based upon three principles:-radial stator cooling of quite novel type, using about 100, 000 narrow ducts distributed in the magnetic core and formed by special way of cutting out and stacking the magnetic punchings,-complete independence of stator and rotor gas circuits in spite of radial stator cooling, the hot air flowing from the field coils back to the rotor spider,-transverse cooling of rotor winding. This new cooling system has been successfully applied to the eight 54 MVA generators of Rock Island and allows 100 MW bulb units to be contemplated.