A 13-level switched-capacitor-based multilevel inverter with reduced components and inrush current limitation

Area of Science:

• Electrical Engineering
• Power Electronics
• Renewable Energy Systems

Background:

• Multilevel inverters are crucial for high-power applications.
• Traditional switched-capacitor inverters often suffer from high component counts and complex control.
• Achieving efficient and reliable capacitor balancing remains a challenge in switched-capacitor topologies.

Purpose of the Study:

• To propose a hybrid switched-capacitor inverter topology.
• To reduce the number of components and simplify control.
• To achieve automatic, sensor-free capacitor balancing.

Main Methods:

• A hybrid structure combining switched capacitor (SC) and flying capacitor (FC) units was developed.
• The design integrates eleven switches and three capacitors to generate 13 voltage levels.
• Inherent voltage balancing of the flying capacitor simplifies control to six switching signals.

Main Results:

• The proposed 13-level inverter uses fewer components than existing SC inverters.
• It features lower maximum voltage ratings for capacitors and reduced conduction losses.
• Automatic capacitor balancing at 0.5Vdc enables sensor-free operation and cost reduction.

Conclusions:

• The hybrid switched-capacitor inverter offers significant advantages in component reduction and control simplicity.
• It presents a cost-effective and efficient solution for multilevel voltage generation.
• Simulation results validate the proposed structure's performance and benefits.