Optimized multi-timescale energy management strategy of a novel all-electric aircraft power system unit based on decentralized control

Abstract

This paper presents an optimized multi-timescale energy management strategy (MTEMS) for a novel all-electric aircraft (AEA) power system unit, which consists of a hybrid energy storage system comprising super-capacitor (SC), battery and fuel cell (FC), as well as a dual three phase permanent magnet synchronous motor (DTP-PMSM) system serving as the propulsion system. During transient states characterized by rapid load changes, the proposed strategy effectively allocates power from the low-frequency, medium-frequency, and high-frequency domains to their respective units, namely FC unit, battery unit, and SC unit. This power allocation is achieved through decentralized droop control implemented in the proposed MTEMS, ensuring a constant and stable bus voltage throughout the operation. In addition, during the steady-state after the change of the load power, a distributed optimization method of the proposed MTEMS can calculate the ratio of power outputs between the battery and FC to maximize the operational efficiency of the fuel cell while ensuring the battery operates in an economically optimal condition. This ultimately guarantees the entire system operates under optimal operating conditions. The achievement of the output power ratio is attainable through the implementation of decentralized droop control. Finally, a 1 kW experimental platform is constructed to validate the effectiveness of the proposed MTEMS and verify the analytical results.