Silicon rectifiers in brushless machinery

An illustration of the use of rotating silicon rectifiers in brushless machinery is given in application to generators for the B-58 bomber. The evolution of both oil-cooled and air-cooled rotating rectifier assemblies is presented. The use of silicon rectifiers in this application illustrates their operation under the most extreme environmental conditions. In addition to all the usual salt spray, humidity, and shock requirements of the military specifications, the rectifiers were required to withstand centrifugal forces up to 15,000 g (acceleration of gravity) and oil pressures of 400 pounds per square inch, both at ambient temperatures from 150 to 180 C (degrees centigrade). Cells were required to withstand 175 volts in the reverse direction and 40 amperes in the forward direction. The brushless generators incorporating the rotating rectifiers were designed to deliver 40 and 60 kva (kilovolt-amperes).