PARALLEL ACTIVE FILTER DESIGN FOR PHASE UNBALANCED PROBLEMS RESOLUTION IN 3-PHASE ELECTRICAL GRID

Energy quality is a very important in the electrical networks reliability, domestic and industrial equipment security. Indeed, all electrical network can be negatively impacted if the energy quality is poor. This poor quality is generally due to the phase unbalanced problems (cables and equipment warming, rotating machines stopping, equipment destruction, etc.). To solve this problematic, in this work, we first modeled the balanced three-phase network suppling three identical single-phase loads without filter using. Secondly, we modeled an unbalanced three-phase network, with a non-identical single-phase loads and a single-phase fault on phase 2 in two configurations; the three-phase unbalanced networks without filter and parallel active filter using. In this context, we propose an approach based on the SRF method (Synchronous Reference Frame) to solve the unbalanced electrical network phenomena by taking into account the harmonics attenuation generated by non-linear loads at the source side. Finally, we have designed and simulated the different model of balanced and unbalanced networks, with or without active power filter under the Matlab/Simulink environment. The obtained results show our model effectiveness with a net compensation of active energy and unbalanced harmonic distortion rate (THD<5%).