Design a multilevel inverter circuit based on different control structures

Several power circuits and controllers using multilevel structures in electrical power systems have been discussed.With the people increasing in the world, the industries and electric power request have increased.Consequently, power systems become difficult and complex especially with non-linear loads 1.Many industrial applications deal with medium and highpower devices.Therefore, multilevel inverters (MIs) are built to deal with the required power rating of these devices.Also, MIs can produce the required voltage and power with minimum output harmonics by increasing the output voltage levels.MIs can be supported by using renewable energy sources (RESs) 2.The MI has some advantages than the two-level inverter type which involve a decreased dv/dt and increased efficiency 3456.The MI topologies are used to transform the direct current (DC) power to alternating current (AC) power and improve stability, efficiency, cost, and power quality of the system 7.*Author for correspondence Power switches (SW) of MI are the main part that used to converter the input DC constant voltages to different AC voltage levels.They are determined the size of power circuit, connection reliability, control difficulty, and circuit cost.Reducing count of SWs compared to the conventional MIs reduces the size, cost, control complexity, and produce higher output voltage level 8,9.The main challenges of selecting MI's arrangement are developing the power circuits to get high power quality at the required voltage level with less SWs, complexity, and optimum control technique.Different MI structures have been designed, but the cascaded H-bridge MI (CHMI) has gotten more attention.Based on the value of DC sources, the CHMI circuit is categorized into symmetrical MI (SMI) type and asymmetrical (AMI) type.To step-up the output voltage levels in traditional types (SMI), it is required to increase the number of H-bridges, which increases the SWs, gate drives, and protection circuits.In this case, the entire system is complex and costly.