Approaches to analytical analysis of active filter behaviour

Abstract

The paper deals with sample structures of active filters. The aim is the evaluation of an analytical model for analysing the influence that filter parameters have on behaviour of the device. The results give also the opportunity to carry out useful guidelines for filter design. By means of well-known mathematical procedures the traditional mathematical model of active filter is arranged to be suitable of an analytical solution of the system of differential equations. Solutions are expressed as a function of the time and by means of inner parameters. Therefore it is possible a simple evaluation of the influence of the parameter values on output filter currents

An efficient architecture of a PV plant for ancillary service supplying

“…If the total leakage inductance of the transformer is lower than the value given by (11), an additional external inductance is needed, complicating the circuit topology.…”

“…x negligible polluting emissions, because no fossil fuels are utilized; x financial support and aids, that help the diffusion, even if up to now not so extended, in many countries; The transfer of the produced energy to the network, requires a dc/ac converter; a PWM inverter can be considered which for "power quality" reasons needs a filter [8,11,12].…”

Performance Analysis of Active Filters Used for Harmonic Compensation

“…The integration of the third of eqs. (2) gives the expression of Vdc as function of the time: 12fIfdt = rf (ifIf f+ If ) t + 2 N et 2jo'' eit (12) 1)}.…”

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A control algorithm of power converters in smart-grids for providing uninterruptible ancillary services

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