Removal of source current harmonics under Harmonically Balanced Condition using shunt hybrid active filters

Paper is produced to grant a concept regarding the use of shunt hybrid active power filter to counteract the deteriorating effect of harmonics in electrical power utility system. 3-phase uncontrolled bridge rectifier has been used as a source of current harmonics of order 6n±1 where n is an integer, producing Harmonically Balanced Condition by drawing equal magnitude of (6n±1)
^th
current harmonic in each phase. Two shunt hybrid active filters connected at point of common coupling are used to reduce current harmonics through insertion of “Positive Inductance” to tune the passive filter. “PLL Free” approach of harmonics detection is used which reduces the additional hardware cost. Implementation of proposed method is carried out in MATLAB/SIMULINK environment. The description starts with a brief outline of harmonic distortion problems and their effects on electrical system under power quality issues.