High quality rectifiers with reduced thd for enhanced mains power quality`

Abstract

This thesis presents high-efficiency, high-density, high quality converters with reduced THD for enhanced mains power quality for high-power equipments. The increased applications of non-linear loads and reactive loads make harmonic distortion and over loading of power transmission and distribution networks, a phenomenon that is occurring quite often and the effects of which cannot be ignored since almost all the power transmission and distribution newlinenetwork components are affected. More harmonics result in more losses, lower efficiency, newlinemore electric energy to be produced and correspondingly more pollution and particularly more carbon dioxide put in to the atmosphere. Lower harmonics and lower reactive power in transmission networks makes not only an economic sense but also a direct solution for sustainable development. Till now the traditional method of current harmonic reduction involved passive filters LC, parallel-connected to the grid, neither convenient nor economical. However, an attractive alternative to this solution is now commercially available based on power electronics in the form of active PFC front ends and active power filters (APFs). The control strategies have been very complex and specific to each application.