Superconducting Power Filter for Aircraft Electric DC Grids

Abstract

A new device, referred to as Superconducting Power Filter (ScPF), is introduced to improve the stability of aircraft electric DC grids. This device is made of a non-inductive superconducting coil connected in series with a conventional RLC filter. The superconducting coil behaves as a nonlinear current-dependent resistance. By design, the superconductor does not undergo a full transition to the normal-resistive state and remains in the current-sharing regime. Thus, a quick response and recovery of the superconductor to transients can be achieved. In the present work, the thermo-electric model of the device incorporates a refined description of the transition from the superconducting state to the normal-resistive state of the superconductor. To check the feasibility of passive stabilization of embedded DC grids using ScPF, different widths and lengths of commercially available 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> generation High Temperature Superconducting (2G HTS) tapes were considered. We chose a case study simulating an equivalent circuit of a More Electric Aircraft (MEA) with an EPS-A3 architecture. For this particular case study, it is shown that the stability limit of the DC grid can be significantly increased, while preserving the reliability (no quench) and low cost (only a few meters of superconducting tape) of the ScPF.