Novel 3-level Hybrid Neutral-Point-Clamped Converter (original) (raw)
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Increasing focus on green energy generation and environmental ecology, expanding the solar power generation and hybrid electric vehicles practice. Higher demand for Neutral Point Clamped (NPC) converters in green energy generation and environmental protection areas is the main motivation behind the analysis of NPC converter operation for different modulation Indices and frequencies with which IGBT is turned on and off. Sinusoidal pulse width modulation (SPWM) implemented with the aid of MATLAB Simulink tool for threephase NPC converter operation. Each switching element's power losses and temperature are simulated with the Fuji IGBT Simulator tool. The Systematic method of NPC converter, total losses evaluation is presented, and obtained losses are validated with analytical losses. The effect of SPWM and modulation index (MI) on the converter losses, is verified. Variation of converter efficiency as a function of modulation index and frequency of turning on and off is obtained and analyzed. The proposed approach and analysis will suggest the relevant operating mode of a converter for a specific application.