INTERNATIONAL JOURNAL OF PROFESSIONAL ENGINEERING STUDIES Volume II/Issue 2/MAR2014 IJPRES 41 A NOVEL MULTI LEVEL INVERTER TOPOLOGY BY USING SWITCHED CAPACITOR CONNECTION CH. Koteswara Rao 1 , U. Chandra Rao M.Tech 2 , CH. Rambabu M.Tech (Ph.D.) 3 , 1 M.Tech Student, Sri Vasavi Eng College, Tadepalligudem 2 Associate Prof., Sri Vasavi Eng College, Tadepalligudem 3 HOD of EEE Dept, Sri Vasavi Eng College, Tadepalligudem Abstract--In this paper a novel boost switched- capacitor inverter is proposed. The circuit topology was introduced. The modulation method, the determination method of the capacitance, and the loss calculation of the inverter proposed. In this paper, an SC inverter whose structure is simpler than the conventional SC inverter is proposed. It consists of a Marx inverter structure and an H-bridge. The proposed inverter can output larger voltage than the input voltage by switching the capacitors in series and in parallel. The maximum output voltage is determined by the number of the capacitors. The proposed inverter does not have any inductors can be smaller than a conventional two-stage unit which consists of a boost converter and an inverter bridge, which make the system large. The structure of the inverter is simpler than the conventional switched-capacitor inverters. THD of the output waveform of the inverter is reduced compared to the conventional single phase full bridge inverter as the conventional multilevel inverter. In this paper, 11 level circuit configuration, the theoretical operation, and the simulation results with MATLAB / SIMULINK. Index Terms—Charge pump, multicarrier PWM, multilevel inverter, switched capacitor (SC). I. INTRODUCTION Recently, electrical energy systems, electric vehicles (EVs), and dispersed generation (DG) systems, etc., are focused because of the global environmental issues. The power electronics, converters and inverters, is a key technology in these systems. The EVs and the grid connected DG systems need an inverter to convert dc to ac. Boost converters or transformers are widely used in these systems when the input voltage is smaller than the output voltage. However, a transformer or an inductor in the boost converter makes the system large, because the transformer and the inductor must have large and heavy magnetic cores to sustain the high power. As a provision against the issue, a charge pump, which does not have any inductors, is applied to such systems. A charge pump outputs the larger voltage than the input voltage with switched capacitors [6]. When the several capacitors and the input voltage sources connected in parallel, the capacitors are charged. When the capacitors are switched by the switching devices between the capacitors, several capacitors are connected in series and discharged. The voltages of the capacitors are added to the output voltage of the charge pump. However, a charge pump has many switching devices which make the system more complicated. A switched-capacitor (SC) inverter outputs multilevel voltage with switched capacitors [7], [8]. An SC inverter is similar to a charge pump in the topology. The SC inverter can output larger voltage than the input voltage in similar way to the charge pump. However, the SC inverter also has many switching devices which make the system more complicated. On the other hand, a Marx inverter, which is reduced the number of the switching devices compared to the SC inverter, was proposed [9]. It is considered that the Marx inverter is one of the SC inverters because of its operation principle. In this paper, a SC inverter whose structure is simpler than the conventional SC inverter is proposed. It consists of a Marx inverter structure and an H-bridge. The proposed inverter can output larger voltage than the input voltage by switched capacitors in series and in parallel. The proposed inverter does not have any inductors which make the system large. The output harmonics of the proposed inverter are reduced by the multilevel output.