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Transient operating conditions in electrical systems not only have significant impact on the operating behavior of individual components but indirectly affect system and component reliability and life. Specifically, transient loads can cause additional loss in the electrical conduction path consisting of windings, power electronic devices, distribution wires, etc., particularly when loads introduce high peak vs. average power ratios. The additional loss increases the operating temperatures and thermal cycling in the components, which is known to reduce their life and reliability. Further, mechanical stress caused by dynamic loading, which includes load torque cycling and high peak torque loading, increases material fatigue and thus reduces expected service life, particularly on rotating components (shaft, bearings).

Air Force Research Laboratory (AFRL) is pursuing development of advanced, distributed, intelligent, adaptive engine controls and engine health monitoring systems. The goals this pursuit are enhancing engine performance, safety, affordability, operability, and reliability while reducing obsolescence risk. The development of smart, high-bandwidth, high-temperature-operable, wide-range, pressure/temperature multi-sensors, which addresses these goals, is discussed. The resulting sensors and packaging can be manufactured at low cost and operate in corrosive environments, while measuring temperatures up to 2,552 °F (1,400 °C) with simultaneous pressure measurements up to 1,000 psi (68 atm). Such a sensor suite provides unprecedented monitoring of propulsion, energy generation, and industrial systems. The multi-sensor approach reduces control system weight and wiring complexity, design time, and cost, while increasing accuracy and fault tolerance.

Modern propulsion system designers face challenges that require that aircraft and engine manufacturers improve performance as well as reduce the life-cycle cost (LCC). These improvements will require a more efficient, more reliable, and more advanced propulsion system. The concept of smart components is built around actively controlling the engine and the aircraft to operate optimally. Usage of smart components intelligently increases efficiency and system safety throughout the flight envelope, all while meeting environmental challenges. This approach requires an integration and optimization, both at the local level and the system level, to reduce cost. Interactions between the various subsystems must be understood through the use of modeling and simulation. This is accomplished by starting with individual subsystem models and combining them into a complete system model. Hierarchical, decentralized control reduces cost and risk by enabling integration and modularity.