## 1 Introduction  
Conventional power systems are getting degraded due to the gradual reduction in fossil fuels, poor energy efficiency, and low reliability. This leads to the development of new power generation systems at the distribution level using various nonconventional and renewable energy sources such as solar energy, wind power, fuel cells, and biogas [1]. These energy sources are integrated into a utility distribution network; the power generated using this network is termed as distributed power generation, and the energy sources incorporated in this network are known as distributed energy resources (DERs). The penetration of DERs in the worldwide electrical distribution leads to the formation of power clusters which are known as microgrids. This provides an opportunity to utilize renewable energy sources for a green and clean environment [2, 3]. Furthermore, the DC microgrid has advantages such as high reliability, uninterruptible power supply, no reactive power, reduced losses, higher efficiency, simpler connection with DC bus, no need of synchronization, and no frequency aspects. Despite advantages over alternating current microgrids, the output voltage of these DC power generators is low. Therefore, high-gain DC-DC converters are needed for a DC microgrid [4]. Moreover, the use of multilevel inverters has become predominant in the fields of power systems, solid-state transformers,power quality conditioning, renewable energy applications, and many more industrial applications. Among these, PV-based power generation systems are gaining popularity and are widely used in distribution-side networks. The process of power generation is classified into on-grid and off-grid systems, and the role of inverters is inevitable in all grid-connected networks. Initially, two-level inverters are employed in grid operation for the conversion of voltage from PV arrays to the grid network. However, the efficiency and conversion gain of these conventional inverters is much lower, which results in poor power quality issues and harmonics. To overcome these problems, multilevel converters have been introduced for combining PV arrays with the distribution grid [5, 6]. Multilevel inverters possess better characteristics when compared to conventional two-level inverters [7, 8, 9]. The merits of MLI topologies include a better harmonic profile, reduced filter size, modular structure, improved load sharing capabilities, and reduction in voltage stress levels across the switches [10]. Many researchers working in this domain are trying to contribute a novel configuration with improved efficiency, power density, and reliability at a low cost. The studies published by many researchers working in this field have proven that the modifications of NPC (neutral point clamped), cascaded H-bridge topologies give greater efficiency with reduced harmonic content [11]. The types of multilevel inverter are illustrated as a schematic in Figure 1.  
Overall, this work focuses on power electronic converters such as DC-DC converters and inverters for applications associated with the DC microgrid. An illustration of the proposed system is shown in Figure 2. The input is fed from a PV array and is given to a novel single-switch non-isolated high-gain DC-DC converter to match with the DC bus voltage level. It can also supply AC loads via the modified 11-level inverter proposed in this work. The switching logic of the proposed multilevel inverter can also be extended to higher-level configurations and is verified in the simulation environment. To match the output voltage of this converter with the DC bus voltage, a suitable PI controller is designed, providing a better control operation. The analysis is performed and the results are obtained with the help of MATLAB simulations. To validate the simulation results of the multilevel inverter, a prototype for five-level configuration is developed and tested in the laboratory. Figure 1: Multilevel inverter classifications.