This course includes information necessary for the proper design of 400-Hertz (Hz) conversion, distribution, and utilization systems. Special regard is paid to systems utilizing medium-voltage distribution. Systems supplying 400 Hz for ground-power operations use frequency conversion equipment to change 60-Hz input to 400-Hz output. Rotary converters (motor generator sets) or solid state converters are used for this purpose. Fixed service point units to which avionics equipment and aircraft are connected are supplied from either nearby frequency conversion assemblies over a low-voltage feeder system or from a more remotely located 400-Hz central plant using medium-voltage feeders. Course Outline< br/> 1. INTRODUCTION 2. GENERAL CONSIDERATIONS 3. DESIGN REQUIREMENTS

Learning Objectives

• Learn about rotary converters and motor generator sets are used for both low and medium voltage systems;
• Learn how to employ solid state converters for low-voltage systems;
• Learn about flight-line electrical distribution sets (FLEDS) used in conjunction with the low-voltage or medium-voltage systems;
• Find out about the inductive contribution to the reactance voltage drop of 400-Hz systems which necessitates certain modifications to conventional distribution and utilization system design to compensate for the increased voltage drop.
• Learn about acceptable end-voltage requirements;
• Learn about maximum cable length limitations; and
• Learn the fundamentals of system layout..