DOI link for Phase-Shifting Transformers
Phase-Shifting Transformers book
Tools in the form of phase-shifting transformers (PSTs) are available to control the power flow to stabilize the grids. Now phase-shifting is quite a normal condition for a transformer and can be found in every transformer that incorporates differently connected primary and secondary windings. Quadrature booster transformers are a combination of a regulating power- or auto-transformer with a PST. In general, the design characteristics of PSTs do not differ from ordinary power transformers. In the symmetrical case, however, the phase-angle difference of the currents flowing through the two parts of the series winding has to be recognized. In case of a two-tank design, the PST should be completely assembled with the two units connected together, as in service. Auxiliary bushings may be necessary to make inner windings accessible for measurements of resistances, losses, and temperatures or to allow dielectric tests.