Current Sensor-less Predictive Load Voltage Control for Four-leg Inverter with LC Output Filter

The conventional finite-control-set model predictive control (FCS-MPC) for a four-leg inverter with LC output filter requires measurements of load voltage, load current, and inverter current to select the optimal voltage vector which leads to a high number of sensors for the control implementation. To simplify the predictive control implementation, this paper presents a current sensor-less FCS-MPC scheme for predictive load voltage control of four-leg inverter with LC output filter. To eliminate the current sensors, a Luenberger observer based simple capacitor current estimator is employed in this work. The implementation of a current sensor-less scheme for four-leg inverter not only reduces the implementation cost but also enhance the reliability of the controller. Simulation and experimental results in different test conditions are shown to assess the performance of the proposed control scheme. Results also confirm that the proposed method can achieve comparable performance with the conventional FCS- MPC scheme while eliminating the need for current sensors.