The Future of 400 Hz Power Systems (Present Interface Problems and Solutions),

The long-term solution for the 400 Hz system problems is to eliminate the use of 400 Hz entirely except where 400 Hz is required in the end use. Most 400 Hz power is simply rectified in transformer-rectifier power supplies. New developments in power supply design techniques indicate that 60 Hz power supplies smaller, lighter and more efficient than present 400 Hz power supplies are feasible. Further, the elimination of the 60400 Hz frequency changers saves weight, volume, and cooling load, and provides a more reliable power source for weapons and electronics. Eliminating the 400 Hz power system is at least ten years away. The mid-term solution is to use frequency changers of the solid-state type. Methods of reducing the harmonic and modulation interference both in the load and on the system are available and are being incorporated in new specifications for load equipment and in the U.S. Navy standard solid-state frequency changers. At the present time, systems are working by virtue of isolating interfering and sensitive loads through the use of large numbers of motor generator sets.