Buck-type Single-phase AC-AC Active Tracking Voltage Regulator Controlled by an Enhanced Hybrid Control Method

Abstract

In this paper, a single-phase switch-mode buck-type AC-AC voltage regulator is presented with reduced numbers of elements which are used in the topology. Apart from similar studies in the literature, a new hybrid control method which is structured by the closed-loop PID controller and a new enhanced feedforward controller is used for the control of the regulator. The hybrid controller improves the active tracking capability of the reference to achieve an output voltage as close to the sine-wave with high quality. The input AC voltage may be an ideal sine wave or it may include harmonics. Both simulation and experimental tests are applied for the proposed regulator controlled by this control method. The experimental set-up for the regulator is designed for 0-200 Vp input voltage (50 Hz), 0-100 Vp output voltage, and 0.6 kW output power. The results proved the capability of the proposed buck-type switch-mode regulator to achieve the requested output voltage as near as possible to sine wave. The obtained output voltages for different load conditions and input-output parameters have less than 5% THD (total harmonic distortion) and high quality.