International Journal of Engineering Research

P. T. Krishna Sai ¹, I. Sairam ¹

Affiliations
1 EEE Department, Dhanekula Institute of Engineering and Technology, Vijayawada, IN

Abstract

Power quality is the major concern in today’s electrical power system. Especially, power quality problems are continuously observed in distributed electrical power system. Mainly the voltage quality is the major aspect in distributed electrical power system. Voltage sags and voltage swells are the main parameters on which the improvement is needed. Voltage quality can be sufficiently improved in distributed electrical power systems by using some custom power devices. One of such active filter is dynamic voltage restorer. The Dynamic Voltage Restorer (DVR) is fast, flexible and efficient solution to voltage sag and voltage swell problems. The DVR is a power electronic based device that provides three-phase controllable voltage output, whose voltage vector-magnitude and angle adds to the supply voltage during sag event, to restore the load voltage to pre-sag conditions. And when voltage swell occurs DVR injects 1800 out of phase voltage into the line. The DVR is designed for protecting the whole plant with loads in the range of some MVA. The DVR can restore the load voltage within few milliseconds.

Keywords

Custom Power Device, Dynamic Voltage Restorer, Voltage Sag, Voltage Swell.

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P. T. Krishna Sai ¹, Mahammad Iliyas ²

Affiliations
1 Department of Electrical and Electronics Engineering, Dhanekula Institute of Engineering and Technology, A.P, IN
2 King Khalid University, SA

Abstract

This paper deals with 11-level multilevel inverter. Almost all the drawbacks of the conventional multilevel inverters is rectified by the proposed topology. This topology uses less number of switches as compared with conventional topology, where it reduces the complexity and overall size of the system which in turn reduces the harmonics and cost of the entire system. Fewer switches will be conducting for specific time intervals so switching loss is also reduced in the proposed topology. A 11-level inverter simulation is carried with the implementation of nearest level control. The proposal is validated by extensive simulation studies.

Keywords

Multilevel Inverter, Cascaded Multilevel Inverter, Total Harmonic Distortion (THD).

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