Informatics Publishing Limited

Vinoth Kumar N. ¹, Kumar Chinnaiyan V. ², Pradish M. ³, Divekar M. S. ⁴

Affiliations
1 *Senior Research Fellow, Central Power Research Institute, Bangalore - 560080, IN
2 Professor & Head, KPR Institute of Engineering Technology, Coimbatore - 641407, IN
3 Engineering officer, Central Power Research Institute, Bangalore - 560080, IN
4 Consultant in R&D, Central Power Research Institute, Bangalore - 560080, IN

Abstract

Multilevel inverter is an attractive alternative for traditional two level inverter. It has many advantages over traditional multilevel inverter such as lesser voltage stress on switches, lesser filtering requirement and is free from electromagnetic interference EMI issues. It is being applied successfully in various medium power application such as AC power supplies, drive systems, and Distributed Energy Resources area (DER). In this paper, a review of multilevel inverter is addressed such as various traditional topologies, reduction of power switches,modulation, control strategies, and application. The control and modulation techniques such as Pulse Width Modulation (PWM) Techniques, space vector modulation (SVM) are described. Selective Harmonic Elimination (SHE) with mathematical modelling is addressed in detail. SHE-PWM is preferable as it operates at very low frequency and eliminate the lower order harmonics without any filtering circuit and reduction of switch count ensures higher efficiency with reduction of cost.

Keywords

Multilevel Inverter, PWM Techniques, Reduction of Switches, Space Vector Modulation, Application

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Elanchezhian P. ¹, Kumar Chinnaiyan V. ², Sudhir Kumar R. ¹

Affiliations
1 Energy Efficiency and Renewable Energy Division, Central Power Research Institute, Bangalore - 560080, IN
2 Professor & HOD, EEE Department, KPR Institute of Engineering and Technology, Coimbatore-641047, IN

Abstract

Thepresence of Distributed Resources (DR) and the subject of Distributed Generation (DG) are rapidly growing in modern distribution networks. Many of these resources use renewable energies, and many of them provide electrical energy in the form of dc voltage source. Consequently, the connection of such resources to the utility grid needs a dc/ac conversion stage. Voltage Source Converters (VSC) are widely used for this application as they have a mature technology. These converters are usually connected to the utility grid through a simple L filter to reduce the current harmonics injected to the grid. However, higher order filters, like LCL filters, can provide better harmonic attenuation and reduce the filter size at the same time. This paper proposes a method for LCL type filter design, which makes the task very convenient. Step-by-step design procedure is described as a design example, which is verified by simulation.

Keywords

L, LCl, PCS, Micro-inverter, MIC,PWM

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Elanchezhian P. , Kumar Chinnaiyan V. , Sudhir Kumar R.

Abstract

In this paper two stage boost photovoltaic micro inverter system using maximum power point tracking is presented. First the photovoltaic module is analyzed using SIMULINK software. The main aim of the paper is the boost converter with microinverter to be used along with a Maximum Power Point Tracking control mechanism. The MPPT is responsible for extracting the maximum possible power from the photovoltaic and feed it to the load via the boost converter which is used to steps up the voltage to required magnitude. Both the boost converter, and the solar cell are modelledusing Sim Power System blocks. Here the voltage source inverter is cascaded and it injects sinusoidal current to the grid. The dynamic stiffness are obtained when load or solar insolation changing rapidly. This paper investigates in the detail concept of Maximum PowerPoint Tracking (MPPT) which significantly increases the efficiency of the solar photovoltaic system.

Keywords

Boost Converter, Grid Connected Photovoltaic (PV) System, Voltage Source Inverter, Maximum Power Point Tracking (MPPT), Pwm Generator.

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