A New Simple Single Phase AC-AC Switching Voltage Regulator Cum Power Conditioner

A new very simple single phase ac-ac voltage regulator based on LC network is proposed here that compensates wide range supply voltage variations. This has the capability of both buck and boost the input source voltage level without any change of phase angle. The number of components used in the converter circuit is minimum and smooth output waveform can be achieved without any additional filter. The proposed system employs two bidirectional switches having high frequency pulse width modulation (PWM) and one LC network along with a simple closed loop control. The source voltage level can be sensed and divided by the desired output value to find the instantaneous value of gain, which mathematically calculates the possible duty ratio of PWM switching signal based on the open loop characteristics of the converter. High speed IGBTs are used as bi-directional switch of the ac-ac converter and the circuit ultimately can easily and steadily maintain regulated voltage supply across the load terminals. The whole system operating principle and analysis are presented in this paper. Simulation and experimental results confirm the quality steady output both in dynamic and steady state conditions. Keywords–LC network, pulse width modulation, ac regulator, power conditioner.