Hierarchical Multi-Timescale Energy Management for Hybrid-Electric Aircraft

2020 ◽  
Author(s):  
Wenqing Wang ◽  
Justin P. Koeln
Keyword(s):  
Power Systems ◽  
Constraint Satisfaction ◽  
State Constraint ◽  
Computationally Efficient ◽  
Hybrid Power Systems ◽  
Electrical Systems ◽  
Electric Aircraft ◽  
Aircraft Performance ◽  
Hybrid Electric ◽  
Upper Level

Abstract Hybrid-electric aircraft represent an important step in the transition from conventional fuel-based propulsion to fully-electric aircraft. For hybrid power systems, overall aircraft performance and efficiency highly depend on the coordination of the fuel and electrical systems and the ability to effectively control state and input trajectories at the limits of safe operation. In such a safety-critical application, the chosen control strategy must ensure the closed-loop system adheres to these operational limits. While hierarchical Model Predictive Control (MPC) has proven to be a computationally efficient approach to coordinated control of complex systems across multiple timescales, most formulations are not supported by theoretical guarantees of actuator and state constraint satisfaction. To provide guaranteed constraint satisfaction, this paper presents set-based hierarchical MPC of a 16 state hybrid-electric aircraft power system. Within the proposed two-level vertical hierarchy, the long-term control decisions of the upper-level controller and the short-term control decisions of the lower-level controller are coordinated through the use of waysets. Simulation results show the benefits of this coordination in the context of hybrid-electric aircraft performance and demonstrate the practicality of applying set-based hierarchical MPC to complex multi-timescale systems.

scholarly journals Optimal energy management for hybrid-electric aircraft

2020 ◽  
Vol 92 (6) ◽  
pp. 851-861 ◽  
Author(s):  
José Pedro Soares Pinto Leite ◽  
Mark Voskuijl
Keyword(s):  
Power Systems ◽  
Energy Management ◽  
Gas Turbines ◽  
Weight System ◽  
Content Type ◽  
Optimal Energy ◽  
Variable Weight ◽  
Electric Aircraft ◽  
Optimal Energy Management ◽  
Hybrid Electric

Purpose In recent years, increased awareness on global warming effects led to a renewed interest in all kinds of green technologies. Among them, some attention has been devoted to hybrid-electric aircraft – aircraft where the propulsion system contains power systems driven by electricity and power systems driven by hydrocarbon-based fuel. Examples of these systems include electric motors and gas turbines, respectively. Despite the fact that several research groups have tried to design such aircraft, in a way, it can actually save fuel with respect to conventional designs, the results hardly approach the required fuel savings to justify a new design. One possible path to improve these designs is to optimize the onboard energy management, in other words, when to use fuel and when to use stored electricity during a mission. The purpose of this paper is to address the topic of energy management applied to hybrid-electric aircraft, including its relevance for the conceptual design of aircraft and present a practical example of optimal energy management. Design/methodology/approach To address this problem the dynamic programming (DP) method for optimal control problems was used and, together with an aircraft performance model, an optimal energy management was obtained for a given aircraft flying a given trajectory. Findings The results show how the energy onboard a hybrid fuel-battery aircraft can be optimally managed during the mission. The optimal results were compared with non-optimal result, and small differences were found. A large sensitivity of the results to the battery charging efficiency was also found. Originality/value The novelty of this work comes from the application of DP for energy management to a variable weight system which includes energy recovery via a propeller.

Integrated Propulsive and Thermal Management System Design for Optimal Hybrid Electric Aircraft Performance

2020 ◽  
Author(s):  
Philip C. Abolmoali ◽  
Adam B. Donovan ◽  
Soumya S. Patnaik ◽  
Patrick McCarthy ◽  
Dominic Dierker ◽  
...  
Keyword(s):  
System Design ◽  
Thermal Management ◽  
Management System ◽  
Thermal Management System ◽  
Electric Aircraft ◽  
Aircraft Performance ◽  
Hybrid Electric

scholarly journals Perspectives and Development of Electrical Systems in More Electric Aircraft

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Ahmet Yigit Arabul ◽  
Emre Kurt ◽  
Fatma Keskin Arabul ◽  
İbrahim Senol ◽  
Martin Schrötter ◽  
...  
Keyword(s):  
Power Systems ◽  
Electric Propulsion ◽  
State Of The Art ◽  
Aircraft Design ◽  
The State ◽  
Total Change ◽  
Profound Change ◽  
Electrical Systems ◽  
Electric Aircraft ◽  
More Electric Aircraft

On-board electrical systems are the key components of each modern aircraft. They enable its safer, more comfortable, and environmentally friendlier operation. The strict regulations to reduce pollution and noise are produced by aircraft eventuated in projects like Clean Sky or ICAO Global Coalition for Sustainable Aviation. One solution to environmentally friendlier operation is the full electric propulsion of the aircraft, which enables the reduction of both noise and pollution. Such a concept requires a total change of all on-board power systems and enables the profound change in aircraft design. This paper presents the evolution of aircraft power systems into the so-called more electric aircraft (MEA) and discusses the state-of-the-art electrical systems. Furthermore, the concept of all-electric aircraft (AEA) is presented here.

Synergistic hybrid-electric liquid natural gas drone: S.H.I.E.L.D

2020 ◽  
Vol 92 (5) ◽  
pp. 757-768 ◽  
Author(s):  
Thierry Sibilli ◽  
Capucine Senne ◽  
Hugo Jouan ◽  
Askin T. Isikveren ◽  
Sabrina Ayat
Keyword(s):  
Thermal Management ◽  
Synergistic Effects ◽  
Energy System ◽  
Sensitivity Study ◽  
Coolant Temperature ◽  
Electrical System ◽  
Content Type ◽  
Electric Aircraft ◽  
Aircraft Performance ◽  
Hybrid Electric

Purpose With the objective to assess potentially performant hybrid-electric architectures, this paper aims to present an aircraft performance level evaluation, in terms of range and payload, of the synergies between a hybrid-electric energy system configuration and a cryogenic fuel system. Design/methodology/approach An unmanned aerial vehicle (UAV) is modeled using an aircraft performance tool, modified to take into account the hybrid nature of the system. The fuel and thermal management systems are modeled looking to maximize the synergistic effects. The electrical system is defined in series with the thermal engine and the performance, in terms of weight and efficiency, are tracked as a function of the cooling temperature. Findings The results show up to a 46 per cent increase in range and up to 7 per cent gain on a payload with a reference hybrid-electric aircraft that uses conventional drop-in JP-8 fuel. The configuration that privileges a reduction in mass of the electric motors by taking advantage of the cryogenic coolant temperature shows the highest benefits. A sensitivity study is also presented showing the dependency on the modeling capabilities. Practical implications The synergistic combination of a cryogenic fuel and the additional heat sources of a hybrid-electric system with a tendency to higher electric component efficiency or reduced weight results in a considerable performance increase in terms of both range and payload. Originality/value The potential synergies between a cryogenic fuel and the electrical system of a hybrid-electric aircraft seem clear; however, at the present, no detailed performance evaluation at aircraft level that includes the fuel, thermal management and electric systems, has been published.

Sign in / Sign up

Export Citation Format

Share Document