A SYSTEM AND A METHOD FOR TRANSFERRING POWER BETWEEN A MASTER CONTROL UNIT AND A LOCAL CONTROL UNIT COUPLED TO AN ENERGY STORAGE STRING

An energy storage system including an energy storage string formed by rechargeable cells connected in series and an energy management device including a master control unit and at least a first local control unit associated to a first rechargeable cell. A storage string connecting circuit is coupling a positive string terminal with a negative string terminal and a cell connecting circuit is coupling a positive and a negative cell terminal of the first rechargeable cell. The storage string connecting circuit includes a first capacitor device forming with the energy storage string a first closed-loop LC-circuit, and/or the cell connecting circuit includes a second capacitor device forming with the first rechargeable cell a second closed-loop LC-circuit. A master AC signal generator and a local signal generator are configured for generating a first and a second AC pulse in respectively the storage string connecting circuit and the cell connecting circuit.