A quad DC source switched three-phase multilevel DC-link inverter topology

Area of Science:

• Electrical Engineering
• Power Electronics

Background:

• Cascaded multilevel inverters (MLIs) are effective for generating quality output voltage in low-to-medium power applications.
• MLIs shape output voltage into multiple steps, approximating a sinusoidal waveform using multiple DC sources.
• A key challenge in MLIs is the increasing number of components with higher voltage levels.

Purpose of the Study:

• To propose a novel three-phase MLI design utilizing isolated quad voltage source modules.
• To reduce the number of switching components in the current conduction path.
• To enhance the quality of the output voltage.

Main Methods:

• A new three-phase MLI topology is designed, incorporating isolated quad voltage source modules and an H-Bridge inverter.
• Simulations were performed using Matlab/Simulink to analyze operational features.
• An experimental module was constructed to validate simulation results.

Main Results:

• The proposed design demonstrates reduced switching components for current conduction.
• Improved output voltage quality, characterized by lower THD (Total Harmonic Distortion), was observed.
• Simulated and experimental results confirm the effectiveness of the proposed MLI design.

Conclusions:

• The novel cascaded MLI design offers a viable solution for low-medium power applications requiring high-quality output voltage.
• The design effectively mitigates the component count issue associated with traditional MLIs.
• The reduced component count and enhanced output quality make this design advantageous for practical implementation.