CASCADED MULTILEVEL INVERTER DESIGN FOR MEDIUM VOLTAGE MOTOR DRIVERS

This study aims to simulate and design topology and provide a solution in an efficient Medium Voltage Drive (MVD) suitable for medium and high power applications. A systematic evaluation and comparison of motor drive application and three-phase AC-AC inverters using conventional silicon or silicon carbide power semiconductors is made to achieve this. It is necessary to provide a comprehensive and detailed review of where MVD technology stands and where it is going, to follow the current state and trends of the technology and to group and review its latest contributions. The eleven-level Cascade H-Bridge (11S-KHK), a prototype of five series-connected H-bridge inverters, was designed, implemented and tested, as will be explained in more detail. The main aim of this work was to create the 11L-KHK prototype, a small-scale inverter model that will be part of the drive system for an induction motor in the future. The specifications of the desgıned device are output voltage, three-phase, Vout= 320V and output current Iout= 2A. The hardware phase must be carried out to achieve this goal, and appropriate inverter control techniques must be applied. To create a prototype, it is necessary to start the analysis from the KHK inverter architecture topology and submodules. After selecting the prototype architecture, components such as switches, power supplies and sensors must be chosen. Next, the printed circuit board (PCB) needs to be designed onto which the pre-selected components will be glued and electrically connected. This may be the main challenge of this study. For the subsequent extension of these techniques to the induction motor drive system, appropriate control strategies should be applied to interface the inverter to the electrical machine, aiming for good output quality and a fast and stable control response. Önerilen çalışmanın önemli amacı, verimli bir optimizasyon algoritması kullanan optimal bir kontrol tekniği kullanarak çok seviyeli eviricilerin performansını arttırmaktır. This thesis aimed to create a small-scale model of an inverter that will be part of the drive system for an asynchronous motor. The inverter topology and architecture were examined to achieve this, along with possible voltage and current control strategies. It simulates a multi-level inverter that operates efficiently under all operating conditions of the inverter. It analyzes the effect of a multi-level modulation strategy on input current and output voltage harmonic content. The design of a multi-level inverter model to improve power quality using a new modulation technique. Using the concepts and limitations from the literature review, a new objective function using Teaching-Learning Based Optimization (TLC) is proposed to improve the power quality of multi-level inverter. The proposed function outperforms all other existing functions. The results and information provided will help ensure future progress on this project.