This paper proposes a novel switching method with the neutral-point voltage control in a single-phase neutral-point-clamped three-
level inverter (SP-NPCI) used in photovoltaic systems. A proposed novel switching method for the SP-NPCI improves the efficiency.
The main concept is to fix the switching state of one leg. As a result, the switching loss decreases and the total efficiency is improved.
In addition, it enables the maximum power-point-tracking operation to be performed by applying the proposed neutral-point voltage
control algorithm. This control is implemented by modifying the reference signal. Simulation and experimental results provide
verification of the performance of a novel switching method with the neutral-point voltage control.