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Efficient Hybrid Carrier Based Space Vector Modulation for a Cascaded Multilevel Inv - Printable Version +- Free Academic Seminars And Projects Reports (https://easyreport.in) +-- Forum: Seminars Topics And Discussions (https://easyreport.in/forumdisplay.php?fid=30) +--- Forum: Miscellaneous Seminars Topics (https://easyreport.in/forumdisplay.php?fid=21) +---- Forum: General Seminar Topics (https://easyreport.in/forumdisplay.php?fid=58) +---- Thread: Efficient Hybrid Carrier Based Space Vector Modulation for a Cascaded Multilevel Inv (/showthread.php?tid=61413) |
Efficient Hybrid Carrier Based Space Vector Modulation for a Cascaded Multilevel Inv - [email protected] - 10-06-2017 Efficient Hybrid Carrier Based Space Vector Modulation for a Cascaded Multilevel Inverter [attachment=16906] INTRODUCTION Multilevel inverters have become a popular choice in recent years, because improving the output waveform of an inverter reduces its respective harmonic content and, hence, the size of the filter used and the level of electromagnetic interference (EMI) generated by the switching operations [1]. Various multilevel converters structures are reported in the literature, and the cascaded multilevel inverter appears to be superior to other multilevel structures in applications at high power ratings due to its modulation, control and protection of each full bridge inverter [2]. The power circuit for a five level cascaded inverter topology, shown in Fig. 1, is used to examine the proposed PWM technique. HYBRID CARRIER BASED SPACE VECTOR MODULATION DEVELOPMENT The principle behind this hybrid modulation is to mix fundamental frequency PWM and carrier based space vector modulation for each inverter module of a cascaded multilevel inverter. Therefore, the output contains the features of fundamental frequency PWM and CBSVM. In this modulation technique, the four switches of each inverter module are operated at two different frequencies, two being commutated at the fundamental frequency, while the other two switches PERFORMANCE ANALYSIS A. Spectral Analysis of the output voltage and current waveform The performance index namely the current total harmonic distortion (THDi) and the weighted total harmonic distortion (WTHD) are chosen for the quantification of the proposed hybrid CBSVM. The weighted total harmonic distortion (WTHD) is superior to the THD as a figure of merit for a nonsinusoidal inverter waveform in which the lower portion of the frequency spectrum is weighted heavily, are pulse width modulated at CBSVM. |