AC voltage regulators review

AC voltage regulators with or without a transformer review is provided. Several research directions by creation of new AC-AC converters are distinguished, such as voltage stabilization, voltage regulation to nominal values and also increasing of voltage with gain greater than unity, reactive power compensators, active filters, voltage dips and overvoltage compensators and soft start of electric motors devices. Actual solutions of such converters are considered, in each of them could prevail such qualities as high efficiency, reliability, small size and cost.