Modeling and Analysis on PWM Techniques for AC Voltage Controllers

AC voltage controllers are often used to change the output AC voltage from fixed input AC voltage for many industrial and commercial applications by using single stage of conversion. AC voltage controllers provide better replacement of auto transformers with low cost. But their output voltage is not much qualified then auto transformers. To obtain variable and improved output voltages, different Pulse Width Modulation (PWM) techniques have been used. In this paper analysis the different PWM techniques of AC voltage controller is simulated and the results are shown with performance comparison. This is done to show that which PWM technique is more applicable for AC voltage controllers. Phase angle control, single PWM, multiple PWM and sinusoidal PWM techniques are considered for analysis. The analysis and modeling of each technique is compared with output waveforms, tabulated readings and THD graphs. Modeling is performed by using MATLAB/SIMULINK environment.