Experimental validation of a hybrid emergency network with low and medium voltage Li-Ion batteries for more electrical aircraft

This paper deals with a hybrid electrical network for an aircraft in emergency operation. The principle of this network is to hybridize, through a bidirectional DC/DC converter, a high speed Ram Air Turbine (RAT) with an electrochemical Lithium Ion accumulator. A design study of DC/DC power converters, according to the voltage of the accumulator, is presented. The results of this study have shown that utilization of a medium-voltage battery can be a good mass / efficiency trade off of the overall system. Some experiments on a lab test bench have allowed validating the principle of the hybridization and several energy management strategies have been tested with low and medium voltage lithium ion batteries.