A high-performance five-level single-phase inverter using repetitive control and state feedback

In this paper, a novel single-phase five-level inverter is presented to alleviate harmonic components of the output voltage. To keep the output voltage being sinusoidal and to have the high dynamic performance, the paper present a control scheme based on repetitive control with the feedback of the capacitor current. In order to expediently observe the capacitor current, the author uses a dimensionality reduction observer. As we can see from the simulation and the experiment results, the circuit of the inverter is simple, and the output waveform is perfect; even when the load is nonlinear, the waveform just distorts a little