Five-Level E-Type Inverter for Grid-Connected Applications

Nowadays, multilevel converter represents a good idea for commercial and industrial applications, where small size and cost, low maintenance, reliability in a wide range of environments and good efficiency are required. Furthermore, the multilevel converter can provide control for both maximum power tracking and output power factor reducing the filter weight and volume. The proposed power converter topology, called Five-Level E Type Inverter (5L E-Type Inverter), for grid connected applications is presented and analyzed in this paper. The performance of the three-phase 5L E-Type Inverter has been theoretically investigated. The thermal models of the power semiconductor have been created taking into account the parameters provided by the manufactures and employing multi-dimensional look-up tables in Plexim/PLECS environment. The design and selection of passive components have been described in order to obtain amazing performances in terms of weight, volume and efficiency and power quality. New control strategy, named concurrent control, for 5L E-Type Inverter has been implemented and validated in LabVIEW development environment. The peak efficiency of the converter above 98.3% and the total harmonic total harmonic distortion current (THDi) less than 3% have been achieved.