Two-Zone Buck-Boost AC Voltage Regulator

A buck-boost AC voltage regulator is proposed. Currently, much attention is being paid to the quality of electrical energy, which can be improved with the help of power electronics means. Such devices include well-known active filters, STATCOMs, as well as AC voltage regulators. Thus, the proposed scheme makes it possible to compensate for drops and voltage surges of the supply network, without loss of current quality and without adding a reactive component to the supply. At the same time, the solution does not require a complex control system, and voltage regulation is carried out by switching branches with a capacitor and an inductor. The proposed scheme is a two-zone one, where the quality of the output voltage and input current is improved compared to the well-known single-zone regulator circuit. A mathematical model of an AC voltage regulator was constructed using the algebraization of differential equations method. A family of control and load characteristics were obtained from the analytical calculation of the simulation model in the PSIM program. The characteristics of the input shift coefficient, as well as the total harmonic distortion of the input current and output voltage relative to the modulation depth are received. It is shown that the use of a twozone version of the circuit is more efficient in terms of current and voltage quality, which is possible due to the introduction of a phase shift into the transistor control pulses.