Modulated Model Predictive Current Control Technique For Three Phase Five Level Switched Capacitor Based ANPC Grid Connected Inverter with Front End-Multilevel Boost Converter

In the literature, only the standalone operation of a three-phase five-level switched capacitor (SC) based active neutral point clamped-5LSCANPC inverter with level-shifted pulse width modulation (PWM) technique has been explained. This inverter provides unity and double-boosting voltage gains concerning pole and line voltages. In this paper, to obtain quadruple and octuple voltage boosts in the pole and line voltages, a front-end multilevel boost converter (MLBC) has been integrated with the 5L-SCANPC inverter. The consideration of MLBC makes self-balancing of dc-link capacitors and the proper switching action of the inverter makes self-balancing of SCs in all three phases. Conventionally, the finite control set model predictive control (FCS-MPC) technique inherently provides variable switching frequency (VSF) of operation which is unsuitable for industrial applications and is very difficult to design harmonic filters. Hence, to obtain constant switching frequency (CSF) of operation, a modulated model predictive current control (M
²
PC
²
) technique has been proposed. In this technique, a simple floor function (F2) based single carrier PWM (SC-PWM) technique has been used at the end of the modulation stage. The dynamic performance of the proposed technique has been effectively verified in both RL-load and grid-connected operations.