New transformerless AC voltage regulators as devices to improve of power quality

Several approaches to constructing of devices to improve of power quality are offered. In the first and second approaches multizone thyristor AC voltage regulators are offered, new transformerless transistor AC voltage regulators with switches per phase considers in the third, in the fourth approach a new family of buck-boost AC-AC regulators with a common switch are represented, based on the switching of quasi-impedance of power supply with a high frequency. The results of research of proposed regulators are shown.