APPARATUS AND METHOD FOR MANAGING STORED ENERGY
There is provided an apparatus for correcting net energy when providing a load balancing service (50) to an electrical power supply network (30). The load balancing service (50) includes one or more energy storage devices which are charged and/or discharged from energy supplied from and/or to the electrical power supply network (30) respectively, wherein the apparatus associated with the one or more energy storage devices is operable to control their state-of-charge (SOC) as a function of an operating frequency (f) of the electrical power supply network (30), and wherein the apparatus is operable to apply a bias of peak high-excursions and/or low-excursions in frequency for ensuring that the one or more energy storage devices are maintained at nominal charge. Beneficially, the apparatus is operable to employ a piecewise linear control algorithm for managing the state-of-charge (SOC) of the energy storage devices.