access icon free High-efficiency neutral-point-clamped transformerless MOSFET inverter for photovoltaic applications

© The Institution of Engineering and Technology
Received 25/05/2017, Accepted 09/09/2017, Revised 26/08/2017, Published 13/09/2017

Here, a highly efficient MOSFET neutral-point-clamped (M-NPC) transformerless inverter is proposed for photovoltaic (PV) applications. By employing super-junction metal–oxide–semiconductor field-effect transistor (SJ-MOSFET) as well as silicon carbide (SiC) diodes, high efficiency is achieved. Furthermore, the common-mode voltage (CMV) is completely clamped at half of the input voltage with clamping branch. Therefore, leakage current is eliminated. The performances of different topologies, in terms of CMV, leakage current, total harmonic distortion (THD), losses, and efficiency, are compared with the proposed M-NPC topology. The analyses are carried out theoretically via MATLAB/Simulink, and further validated with experimental tests. The experimental results show maximum efficiency of 98.5% and European efficiency of 97.65%.

Inspec keywords: semiconductor diodes; harmonic distortion; silicon compounds; photovoltaic power systems; wide band gap semiconductors; invertors; MOSFET; power system harmonics; clamps

Other keywords: MATLAB-Simulink; M-NPC transformerless inverter; SiC diode; photovoltaic application; common-mode voltage; SiC; PV application; leakage current elimination; super-junction metal-oxide-semiconductor field-effect transistor; efficiency 98.1 percent; CMV; efficiency 98.5 percent; silicon carbide diode; THD; high-efficiency neutral-point-clamped transformerless MOSFET inverter; total harmonic distortion

Subjects: Solar power stations and photovoltaic power systems; Power supply quality and harmonics; DC-AC power convertors (invertors); Insulated gate field effect transistors; Junction and barrier diodes

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