Magazyny energii jako elastyczny zasób wszechstronnie wspierający pracę sieci będą niezbędne, gdy zabraknie pełniących dotąd funkcje regulacyjne elektrowni cieplnych.

Energy storage, as a flexible resource that comprehensively supports network operation, will grow increasingly indispensable as the share of renewables increases.

The paper describes second order generalized integrator (sogi) which is specialized in band-pass filtering and orthogonalization of periodic signals. Modifications of the structure and the influence of parameters on the system performance is described. The article highlights the particular importance of model discretization method in the practical implementation, as well as reviews estimation methods of the: amplitude, frequency, offset and phase angle of the periodic signal. Examples of simulation and experimental results are presented.