Current Control of a New Five-Level Nested T-type Converter with Model Predictive Control

In this paper, a model predictive current control scheme (MPCC) for a new five-level (5L) nested T-type converter (NT2C) is proposed to control output currents and balance the flying capacitor voltages. The 5L NT2C requires fewer components than other 5L converters, which makes the converter more economical and applicable for industrial applications. Compared to the classic sinusoidal pulse width modulation (SPWM) scheme, the MPCC-based method can operate under all power factors and modulation indices. To implement the MPCC scheme, a discrete-time model of the proposed converter is developed considering the switching states. A cost function is then minimized by selecting the optimal switching pattern. The theoretical analysis is verified in the simulation to show the effectiveness of the MPCC for the proposed converter.