Abstract: In the field of high voltage direct current (HVDC) power transmission networks, there is a need for improvements to allow a single power converter to control individual AC network voltages carried by multiple AC transmission conduits to multiple AC network elements, such as respective wind parks.

Abstract: The invention relates to a method for driving the charging and discharging of a plurality of electrical energy storage devices connected to a common connection point (PCC) of an electrical distribution network, as a function of variation of a requested power value (Ptref) at the common connection point, each electrical energy storage device (i) presenting a respective instantaneous state of charge (SOCi), comprising steps of: a—determining a number of electrical energy storage devices needed (Nneeded) to provide the requested power value at a time t, b—activating and/or deactivating one or more of the electrical energy storage devices, as a function of the determined number of electrical energy storage devices needed (Nneeded), and the values of the instantaneous states of charge (SOCi) of each of the electrical energy storage devices (i), and c—distributing the requested power (Ptref) between the activated electrical energy storage devices.

Abstract: In the field of high voltage direct current (HVDC) power transmission networks, there is a need for improvements to allow a single power converter to control individual AC network voltages carried by multiple AC transmission conduits to multiple AC network elements, such as respective wind parks. A power transmission network (10; 100) comprises a power converter (12) which has first and second DC converter terminals (14, 16) that are for connection, in use, to a DC network. The power converter (12) also includes an AC converter terminal (22) which is electrically connected to a plurality of AC transmission conduits (241, 242, 24n), each of which is for connection, in use, to a respective AC network element (261, 262, 26n) that is configured to operate at a respective individual AC network voltage.