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An overview of aircraft DC power quality specifications reveals that only minor changes have occurred in recent years within industry standards. Current and future advanced electronic aircraft are requiring significant power quality improvements due to increased use of digital and COTS (commercial off the shelf) systems. Certain electronic systems do not function properly due to various types of electrical disturbances. Some systems shutdown, fault or exhibit operational delays due to power interruptions or “blackout” conditions. Undervoltage or “brownout” conditions also cause this effect. Some electronic systems exhibit critical faults that can affect safety or mission success due to overvoltage conditions. Additional effects of high voltage spikes or overvoltage transients are known to reduce the life of utilization equipment [1], which is directly related to the health of the aircraft's electronic system and creates an economic burden.

Aircraft utilize electrical power for many functions ranging from simple devices such as resistive heaters to highly advanced and complex systems responsible for communications, situational awareness, electronic warfare and fly-by-wire flight controls. The operational states of these electronic systems affect safety, mission success and the overall economic expense of operation and maintenance. These electronic systems rely on electrical power within established limits of power quality. In recent years, electrical power quality is becoming excessively degraded due to increased usage of nonlinear and dynamic loads coupled to aircraft power systems that were neither designed nor tested for these loads. Legacy power generation systems were designed for electrical loads with resistive and inductive properties, which previously represented the majority of actual aircraft electrical loads.