Computer-aided analysis of stepped sinewave inverters

A stepped sinewave full-bridge inverter was analysed theoretically to determine its optimum working conditions, its minimum number of components, and characteristic of its constituent components and control circuit of its power switches.

A computer program, written in FORTRAN-77, was developed to analyse this inverter circuit. The program prompts for input data such as the characteristics of the power and control circuit elements, the output fundamental frequency, and the number of available batteries and their voltage. The output of the program is designed to give the optimum stair widths, the loss, the harmonic and the total efficiency, the harmonic distortion, the sensitivity of the efficiency and fundamental voltage to the variation in stair width, and the energy withdrawal from each battery for the power switches controlling the circuit. Interesting design data for this circuit were also obtained.