PROJECT TITLE :

Sensor-Less Five-Level Packed U-Cell PUC5 Inverter Operating in Stand-Alone

ABSTRACT:

In this paper, a new mode of operation for packed U-cell (PUC) inverters is presented. For the five-level packed U-cell (PUC5) inverter, which is integrated into the switching process, a sensor-less voltage control based on redundant switching states is devised. The sensor-less voltage control maintains the dc capacitor voltage at half of the dc source value, resulting in a symmetric five-level voltage waveform with minimum harmonic distortion at the output. The suggested converter's sensor-less voltage regulator simplifies the Control System's complexity, making it suitable for industrial applications. For grid-connected application of the introduced sensor-less PUC5, an external current controller has been used to inject active and reactive power from the inverter to the grid with arbitrary power factor, while the PUC auxiliary dc bus is regulated only by sensor-less controller combined with new switching pattern. The proposed PUC5 inverter's experimental results in stand-alone and grid-connected operating modes demonstrate the sensor-less voltage control's fast response and good dynamic performance in balancing the dc capacitor voltage at the intended level.