Efficient Zonal Method Based Comprehensive Modeling and Real-Time Simulation of More Electric Aircraft

• Author / Creator

  Huang, Zhen

• More electric aircraft (MEA) is deemed as next generation aircraft to help simplify system structure, improve reliability and save fuel. A comprehensive real-time simulation model of MEA can benefit the on-going development of the involved technology, and thus is of significance for MEA researchers and designers. The complete MEA model is a high-complexity system and contains multi-domain (electrical, pneumatic, hydraulic, and mechanical) components, which makes it very challenging for analyzing. Therefore, some special modeling techniques and computational strategies have to be created to simplify the solution process.

  This thesis aims at realizing comprehensive modeling and real-time simulation of MEA by utilization of the efficient zonal method (EZM). Thus the accomplished works can be mainly divided into two parts: the design of EZM modeling methodology and the construction of the real-time MEA model.

  The EZM is originated by an attempt to model nonlinearities, especially the switching transients, in power electronic circuit simulation. It is further found that the voltage/current relation of a circuit can be expressed in an antisymmetric matrix form. The proving process of this feature is provided and summarized into a circuit lemma. This feature is the foundation of EZM as it provides a way to find current relation through manipulation of voltage relation, a far less difficult task to accomplish.

  Based on this feature, the EZM modeling methodology for circuit simulation is designed where the computation is divided into two interleaved processes: advancing system variables according to components' characteristics and taking into acount the network response. In this way, the processing of components' characteristics and circuit topology are decoupled and can be dealt with separately.
  The resulting computational complexity reduces to nearly linear with the circuit scale—a significant reduction compared with traditional modeling methods.

  The comprehensive MEA model was then constructed based on the modeling methodology of EZM. The Boeing-787 on board power system is selected as the framework where various components including the pneumatic, hydraulic and mechanical modules are modeled and integrated into the system. Due to the fact that EZM can be viewed as the application of explicit numerical integration methods for solving circuit differential equations and explicit methods usually have relatively small numerical stability regions, the eigenvalue distribution of the assembled system is also analyzed for time-step selection scheme.

  The constructed MEA model was emulated on field programmable gate array (FPGA) and high fidelity real-time simulation was realized. Emulation results from FPGA board and commercial software under several test scenarios coincide with each other to a very high degree, which showcases the efficacy of EZM with
  respect to computational efficiency and ability to accommodate multi-domain models. High agreement on transients waveforms suggests that this EZM based comprehensive MEA model could be a helpful tool for the modeling and design of MEA power system. The proposed circuit lemma and the corresponding EZM are even worth being promoted to model other complex systems that contain large-scale circuit.

• Subjects / Keywords

  • real-time system
  • circuit simulation
  • eigenvalue

• Graduation date

  Spring 2020

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/r3-gkrq-hv74

• License

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