Development of Inverter from a DC Source Using a Polarity Selectable Buck-Boost Converter with Modified Sawtooth Signal

This paper presents the development of an inverter from a single DC source using a polarity selectable buck-boost converter. Due to the nonlinear relation between the reference signal level and the converter gain when using the ordinary sawtooth signal to generate pulse width modulation, the newly modified sawtooth signal has been developed in this research. The exponential approximation is applied to the sawtooth function used for the proposed converter. In addition, the work shows that the peak value of the output sinusoidal voltage can be higher than that of the input DC source. A design example and computer simulation are also given in this paper to confirm the analytical work.