High boost switched capacitor based 13L CG transformerless inverter for cost effective grid integration

Area of Science:

• Electrical Engineering
• Power Electronics
• Renewable Energy Systems

Background:

• Transformerless inverter topologies are crucial for solar photovoltaic and grid-connected systems.
• Common ground features minimize leakage current and improve efficiency.
• Existing topologies often face challenges with voltage gain and cost.

Purpose of the Study:

• To introduce a novel high-boost switched capacitor thirteen-level (13L) common ground transformerless inverter topology (HBSC-13L-CGTLI).
• To achieve a high voltage gain (six) and reduce overall inverter cost.
• To demonstrate superior performance compared to existing 13L inverter topologies.

Main Methods:

• Development of a new HBSC-13L-CGTLI topology utilizing a single DC source, thirteen switches, four switched capacitors, and three diodes.
• Detailed analysis of operational modes, switched capacitor design, filter inductor design, and loss analysis.
• Validation through MATLAB/Simulink simulations and experimental results from a 1 kW laboratory prototype.

Main Results:

• The proposed HBSC-13L-CGTLI achieves a voltage gain of six with reduced switch voltage stress (67% of output voltage).
• The topology eliminates the need for separate negative voltage level generation circuits.
• Simulations and experimental results confirm the topology's effectiveness under various operating conditions.

Conclusions:

• The proposed HBSC-13L-CGTLI topology offers a cost-effective and efficient solution for solar photovoltaic and grid-connected applications.
• It presents significant advantages over existing thirteen-level inverter topologies in terms of voltage gain, cost, and performance.
• The topology effectively suppresses leakage current and enhances energy conversion efficiency.