Conceptual design of battery energy storage for aircraft hybrid propulsion system

The paper presents a conceptual design approach for Energy Storage (ES) devices in advanced hybrid propulsion system for small aircrafts. The study targets operational improvement and reduction of fuel consumption for different flight missions. Power sharing strategies for ES and the engine are proposed for cruise flight phase aiming to maximise the range and/or endurance for the available amount of fuel in the tank. The ES size is designed against the engine performance and the proposed power sharing strategy by optimizing the flight altitude

Learning stable reduced-order models for hybrid twins

The concept of “hybrid twin” (HT) has recently received a growing interest thanks to the availability of powerful machine learning techniques. This twin concept combines physics-based models within a model order reduction framework—to obtain real-time feedback rates—and data science. Thus, the main idea of the HT is to develop on-the-fly data-driven models to correct possible deviations between measurements and physics-based model predictions. This paper is focused on the computation of stable, fast, and accurate corrections in the HT framework. Furthermore, regarding the delicate and important problem of stability, a new approach is proposed, introducing several subvariants and guaranteeing a low computational cost as well as the achievement of a stable time-integration

Learning stable reduced-order models for hybrid twins

The concept of Hybrid Twin (HT) has recently received a growing interest thanks to the availability of powerful machine learning techniques. This twin concept combines physics-based models within a model-order reduction framework-to obtain real-time feedback rates-and data science. Thus, the main idea of the HT is to develop on-the-fly data-driven models to correct possible deviations between measurements and physics-based model predictions. This paper is focused on the computation of stable, fast and accurate corrections in the Hybrid Twin framework. Furthermore, regarding the delicate and important problem of stability, a new approach is proposed, introducing several sub-variants and guaranteeing a low computational cost as well as the achievement of a stable time-integration

Development of aircraft electric starter-generator system based-on active rectification technology

More-electric aircraft (MEA) has become a dominant trend for modern aircraft. On-board MEA, many functions, which are conventionally driven by pneumatic and hydraulic power, are replaced with electrical subsystems. Starting aircraft engines with an electrical motor instead of using pneumatic power from the auxiliary power unit (APU) is one of the major characteristics of future aircraft. This paper presents the development of a novel electric starter-generator system for aircraft applications. The paper describes the main achievements of the project within the key areas including electric machines, power electronic converters, thermal management and overall system control design. The developed prototype has been tested successfully and the test results are presented in this paper

Conceptual design of battery energy storage for aircraft hybrid propulsion system

The paper presents a conceptual design approach for Energy Storage (ES) devices in advanced hybrid propulsion system for small aircrafts. The study targets operational improvement and reduction of fuel consumption for different flight missions. Power sharing strategies for ES and the engine are proposed for cruise flight phase aiming to maximise the range and/or endurance for the available amount of fuel in the tank. The ES size is designed against the engine performance and the proposed power sharing strategy by optimizing the flight altitude

LiBAT: A High-Performance AC Battery System for Transport Applications

The paper proposes a novel battery design for high-performance transport applications that is immersion-cooled and switched by a multi-level inverter. Advantages of the proposed AC battery design in terms of weight, modularity, scalability, performance, reliability and safety are presented. To demonstrate the applicability of the design, an electrically powered glider use case is addressed. The derived battery system is evaluated by means of theoretical analysis, simulation and prototyping. Simulations showed that the used multi-level inverter (MLI) power electronics modules could successfully run the motor without additional power electronics and charge batteries from a 110 V AC source. The prototype implementation with a motor-driven propeller demonstrated power levels of up to 3.3 kW, with a behavior in accordance with simulations. Guidelines to further advance the technology readiness level including control strategies and hardware design were derived to overcome limitations in the prototype realization that could not be addressed within the project budget. Finally, research topics to evaluate additional performance metrics such as efficiency and aging behavior are suggested