Robust Aircraft Electrical Power System Architectures

The move to more-electric architectures during the past decade in military and commercial airborne systems continues to increase the complexity of designing and specifying the electric power system (EPS). The addition of numerous high-power electric loads has drastically altered the dynamics of power flow on the electrical bus. Many of these loads often exhibit peak-to-average power ratios in excess of 5-to-1 for brief periods of time (50-5000 ms). In addition to this high peak-power, some of the loads can produce regenerative power flow equal to their peak power draw for brief periods of time (typically 20-200 ms). In addition to the ever increasing dynamics of electrical loads in the modern fighter, the move to electrify more systems has increased the criticality of the EPS leading to increased need for redundant and configurable systems. In the modern fighter, the resulting reliability requirements have led to EPS architectures wherein multiple sources exist within the aircraft that are dynamically taken in or out of the EPS based upon the failure status of a variety of components. Such reconfiguration is practical in large part due to the aircraft capability to adjust power requirements in response to source limitations by adjusting the performance capabilities of the platform. As the reconfigurability of the EPS, the number of available sources, and the number, complexity, and criticality of system loads continue to increase, several interesting questions arise regarding the design and validation of the EPS including: 1) Will the proposed EPS architecture be stable under all possible configurations of system loads? 2) Does the architecture optimally utilize the variety of source capabilities that exist throughout the aircraft? In this proposal, PCKA outlines a strategy to address these questions by investigating the potential to extend the source control coordination recently developed in relation to electrical accumulator technology to address source utilization and the stability by design concepts outlined in recent controls literature to develop a robust electrical power system (REPS) (potentially including multiple sources and loads) that ensures large-displacement stability of a modern more-electric aircraft (MEA) EPS against any load type. A combination of theoretical development, architectural proposal and analysis, and numerical MS & A shall be utilized to define the framework for stability analysis, define a multi-source architecture, develop a coordinated source control approach, and demonstrate the feasibility of the proposed advancements. Specifically, the tasks outlined in the proposal will be performed at a fidelity required to predict system stability of a representative MEA REPS architecture with sufficient confidence that a Phase II award to investigate system performance in hardware would be justified.