Enhanced Ac-To-Ac Frequency Changer Based on Multi-Phase Smart Comparative Commutation

Direct AC to AC power conversion was always a challenge to be proposed as an alternative for the DC-link one. This is due to multiple of reasons such as less complexity, power regeneration, and unity power factor privileges. However, the challenge is represented by producing a direct AC to AC system with output waveforms having reduced total harmonic distortion comparable or superior to that generated by the DC-link converters. In such a trend this paper introduces an enhanced AC-to-AC frequency changer with reduced total harmonic distortion frequency spectrum compared to the envelope cycloconverter one. This proposed work introduces smart comparative phases switching carried out via a processing unit that detects and measure the analogue voltages of each phase and sends a switching triggers to the power switching circuit. The proposed work reflected an effective reduction in output waveforms harmonic content (about 60%) compared to the envelope cycloconverter with low cost system requirements.

http://www.jee.ro/index.php/jee/article/download/WR1415650386W54611c522ca87/1189