Application of SMES-FCL in Electric Aircraft for Stability Improvement

Abstract

The increase in aircraft passengers and airfreight traffic has given rise to concerns about greenhouse gas emissions for traditional aircraft and the resulting damage to the environment. This has led several companies and organizations, including NASA, to set goals to enhance aircraft efficiency as well as reduce fuel burn, pollution, and noise for commercial aircraft. The most notable electric aircraft (EA) concept is the N3-X, which was developed by NASA to achieve environmental goals while maintaining the annual growth of the aviation industry. However, one of the main challenges that EA facing is their overall weight. This paper proposes and explores an improved power system architecture for use in EA based on the N3-X concept. The number of superconducting magnetic energy storage (SMES) and fault current limiter (FCL) devices required can be reduced by utilizing multifunctional superconducting devices that combine the functionalities of both a SMES and a FCL, thus reducing the weight and cost of the EA by eliminating a complete device. The proposed control technique offers greater flexibility in determining the appropriate size of coils to function as a FCL, based on the fault type. The proposed EA power system architecture including the SMES-FCL devices is modelled in Simulink/Matlab to test the system performance under different failure scenarios. Index Terms-Electric aircraft (EA), fault current limiter (FCL), superconducting magnetic energy storage (SMES), turboelectric distributed propulsion system (TeDP).

Protection System Architecture for All-Electric Aircraft

“…There are different SMES modules for different power systems; however, a voltage sources converter integrated with SMES (VSC-SMES) is the most suitable for a DC network. In [30], a VSC SMES is used to support the load during voltage dip at the aircraft generator and maintain the propulsion system speed at the required level despite the disturbance at the generator side.…”

Utilising SMES-FCL to improve the transient behaviour of a doubly fed induction generator DC wind system

“…In addition, connecting the SC into the rotor side converter or DC link requires one SC per each wind turbine, which will not be a very economically feasible solution with wind farms consisting of many wind turbine units. A new technique proposed to limit faults in DC systems has been described in [24], which uses the entire SC coil in energy storage function under normal operating conditions and only a small part of the coils as a fault current limiter during fault conditions. In addition to using one device to perform two functions, this method avoids the disadvantage of the recovery period of the superconducting fault current limiter as it can be isolated from the circuit after the fault clearance, as will be detailed in section III.…”

Design of a Bidirectional DC/DC Converter for Energy Storage in Electric Aircraft

“…As for energy storage systems (ESSs), one option is to use a Superconducting Magnetic Energy Storage (SMES) system, as they have much higher power density than batteries, supercapacitors, etc., faster response times in milliseconds, very long operational lifetimes, high cycle life, and can satisfy large pulse loads, though its disadvantages include higher cost per kW, relatively high parasitic losses (mostly from using power switches for the chopper circuit), and the obvious need for constant cryogenic cooling [9]- [11].…”

“…While current literature has separately explored using DAB converters for different loads [3]- [6] and some ESSs [8], and SMES integration into systems (terrestrial grids via chopper or hybrid solution for EA) [9]- [11], none have tried to combine both for EA. This paper proposes a methodology to design and control a combined DAB/SMES system for use in EA, presents its operation using the PLECS simulation platform, discusses its implementation, and uses simulations to predict its performance.…”