International Journal of Electrical and Computer Engineering (IJECE) Vol. 8, No. 6, December 2018, pp. 4902~4911 ISSN: 2088-8708, DOI: 10.11591/ijece.v8i6.pp4902-4911  4902 Journal homepage: http://iaescore.com/journals/index.php/IJECE A Sub-Region Based Space Vector Modulation Scheme for Dual 2-Level Inverter System R. Palanisamy 1 , A. Velu 2 , K. Selvakumar 3 , D. Karthikeyan 4 , D. Selvabharathi 5 , S. Vidyasagar 6 1,3,4,5,6 Asst. Prof, Department of EEE, SRM Institute of Science and Technology, India 2 Asst. Prof, Department of EEE, Navodaya Institute of Technology, India Article Info ABSTRACT Article history: Received Aug 16, 2017 Revised Jul 23, 2018 Accepted Aug 9, 2018 This paper deals the implementation of 3-level output voltage using dual 2- level inverter with control of sub-region based Space Vector Modulation (SR-SVM). Switching loss and voltage stress are the most important issues in multilevel inverters, for keep away from these problems dual inverter system executed. Using this proposed system, the conventional 3-level inverter voltage vectors and switching vectors can be located. In neutral point clamped multilevel inverter, it carries more load current fluctuations due to the DC link capacitors and it requires large capacitors. Based on the sub- region SVM used to control IGBT switches placed in the dual inverter system. The proposed system improves the output voltage with reduced harmonic content with improved dc voltage utilisation. The simulation and hardware results are verified using matlab/simulink and dsPIC microcontroller. Keyword: dsPIC microcontroller Dual 2-level inverter Neutral point clamped inverter (NPCI) Sub-region space vector modulation (SR-SVM) Copyright © 2018 Institute of Advanced Engineering and Science. All rights reserved. Corresponding Author: R. Palanisamy, Asst. prof, Department of EEE, SRM Institute of Science and Technology, Kattankulathur, Chennai, India. E-mail: krsplanai@gmail.com 1. INTRODUCTION In recent days, multilevel inverters play an important role in industrial applications, renewable energy systems and various FACTS compensators [1]. The multilevel inverter (MLI) has many advantages like reduced harmonic level, improved output voltage, low EMI problems and output voltage nearly sinusoidal. MLI was introduced to discover the solution to improve voltage ranges of conventional semi- conductors. But the main disadvantages are capacitor balancing, CMV problem and load current fluctuations [2]. Generally for high power applications low switching frequency is prepared to avoid the switching losses in the system. The main drawback in NPCI is dc voltage fluctuations and voltage stress in each switching devices. Many PWM methodologies are implemented to control the power switches place in the multilevel inverters [3]. Based on the PWM method the output voltage of the particular system can be increased. While using multilevel inverters, the number of switches placed in a leg increases due to increasing the level. So that switching pulse generation becomes more complicated, when number of switches increases in a leg. The system [4] used NPC multilevel inverters to reduce the harmonic level and reduce the capacitor balancing problems. The number of switches used in the both 2-level dual inverters is same as in the corresponding 3- level inverter. And the additional diodes used in the NPC inverter is not needed in the VSI inverter, so it saving the number of components used in the system [5]. Also the NPC inverter has problem of capacitor balancing, but it does not exist in the two level VSI inverter. The implementation cost of the system also reduced, when compared to other conventional multilevel inverters. The main advantage of grid connected topology is greatly enhanced fault acceptance, in case any collapse in one inverter system it can discontinue