Analysis and comparison of real-time sine-wave generation for PWM circuits

The paper presents four methods for hardware and software generation in real time of sine waves suitable for PWM circuits. The sine waves are derived from a truncated modified cosine Taylor series, wt(f-wt) function, a digitally filtered trapezoid, and a second-order differential equation. Triplen injection is incorporated by the addition of a defined magnitude triangular waveform of three times the fundamental frequency. Each sine-wave generating technique is implemented, as applicable, in a programmable logic cell array and/or in microprocessor-based software. In each case, the output spectra and total harmonic distortion are compared with computer-simulated results.