Selective Harmonic Elimination Method for Cascaded H-Bridge Multilevel Inverter

Abstract:

This paper presents a selective harmonic elimination (SHE) modulation technique for cascaded H-bridge (CHB) multilevel inverter. The main advantage of the proposed SHE concept is its simple implementation to eliminate the specific order harmonics. The procedures used to achieve the appropriate switching angles are presented. The switching angles are offline computed using the Newton-Raphson method. The SHE scheme of the adopted inverter uses the relationship between the angles and a sinusoidal reference waveform through some combinational logic gates. Theoretical results are verified by the experimental work of a single-phase 7-level CHB inverter employing an Altera DE2 field-programmable gate array (FPGA). Results show the inverter producing an optimum stepped output voltage when selected low-order harmonics are eliminated and the voltage total harmonic distortion (THD) is improved.

• Periodical: Applied Mechanics and Materials (Volume 785)
• Pages: 122-126
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.785.122
• Online since: August 2015
• Authors: Wahidah Abd Halim, Nasrudin Abd Rahim
• Keywords: Harmonic Elimination, Multilevel Inverter, Total Harmonic Distortion (THD)

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