Abstract
In modern power system, with a variety of non-linear power electronic devices of a large number of applications, power quality concern. These devices into the power system harmonics, so that the harmonic power grids have become more polluted and the quality of the deterioration of electrical energy transmission. Thus, the solution to harmonic problems, become increasingly important. Traditional methods of harmonic suppression is the use of passive filter, but it has many defects, such as: filtering properties of the impact of system parameters by a larger number of only the elimination of specific harmonics, may have a parallel resonance with the system, harmonic current increase in overloaded filters, such as lead, making the effect of harmonic suppression affected. In this paper, a new and efficient based on DSP (digital signal processor)-controlled single-phase active power filter.
A new equivalence principle of current control for shunt active power filters is introduced, which has no use for measurement of harmonic and reactive currents of nonlinear loads. This paper analyzes and demonstrates the principle. Simulation results by MATLAB are given to show that the equivalence principle without measurements has many merits such as simpler circuit configuration and algorithm, more exact compensation effectiveness and rapid dynamic response.
Key words: power electronic technique; shunt active power filters; equivalence principle; current control