Configuring Systems for Operation From Three Phase AC Power

High power computing and networking equipment is not new. What is new is that more and more machines are requiring more power than can be easily provided by a single phase ac power feed. This paper reviews the two main ways to provide the needed dc power from three phase ac power sources. The first way is to use true three phase ac input power supplies. The second method, and most common technique, is to use three single phase ac input power supplies with the outputs in parallel. These techniques and their respective advantages and disadvantages are discussed below. The paper concludes with the discussion of another way of using three single phase ac input power supplies that has a simple installation and simple system level hardware at the cost of much more complex power supplies.