Servet TUNCER, YETKİN TATAR, HANİFİ GÜLDEMİR

A SHEPWM technique with constant v/f for multilevel inverters

Bu makale, çok seviyeli inverterler için seçilmiş harmonikleri yok eden darbe genişlik modülasyon (SHEPWM) tekniğinin yeni bir uygulamasını açıklamaktadır. Makalede ilk olarak, sınırlayıcılı optimizasyon tekniği kullanılarak anahtarlama açıları hesaplanır. Bu anahtarlama açıları ile hem temel harmonik kontrol edilebilir ve hem de seçilen harmonikler yok edilebilir. Sonra, bu hesaplanmış anahtarlama açıları kullanılarak; modülasyon indeksi değişkenine göre anahtarlama açılarını hesaplayan denklem kümesi elde edilmiştir. Bu denklemler kullanılarak 5-seviyeli kaskad inverterden üç-fazlı gerilim Elde edilmiştir. Bu gerilim bir asenkron motora uygulanmıştır. Sabit v/f çalışma için asenkron motorun dinamik davranışı incelenmiş ve simülasyon sonuçları verilmiştir.

Çok seviyeli inverterler için sabit v/f özellikli bir SHEPWM tekniği

This paper concern on a new application of selected harmonic elimination pulse width modulation technique (SHEPWM) for multilevel inverters. In this paper, first, the switching angles are calculated using constrained optimization technique. With these switching angles both the fundamental harmonic can be controlled and the selected harmonics can be eliminated. Then, using these calculated switching angles, a set of equation is formed which calculates the switching angles with respect to modulation index. Using this technique three-phase voltage has been obtained from a five-level cascade inverter. This voltage is applied to an induction motor. The dynamic behaviour of the induction motor has been examined for constant v/f operation and the simulation results have been given.

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