Incomplete-phase algorithms for pulse-width modulation of three-phase voltages in frequency control systems of electric drives

Abstract

Aim. This study aims to analyze incomplete-phase algorithms for pulse-width modulation of three-phase voltages in the frequency control of electric drives, focusing on the criterion of minimizing the number of switching keys in the frequency converter. Materials and methods. To study processes pulse-width modulation processes the in frequency control of electric drives, methods of the theory of electric circuits were used. The proposed algorithms are illustrated in figures and can be implemented in MATLAB software environment. Results. The study examines the pulse-width modulation process in frequency control systems for electric drives. It was established that using incomplete-phase pulse-width modulation algorithms is advisable to minimize the number of switching keys in the frequency converter. Various premodulation functions were analyzed, including pulse-width modulation algorithms with uniform and uneven energy loss distribution across the keys. Analytical models of premodulation functions for pulse-width modulation algorithms were developed, incorporating the use of lower keys in the converter half-bridges and alternating inclusion of their upper and lower keys. Conclusion. The results can be applied to the development of algorithms for controlling frequency converters in asynchronous electric drive systems.