Improving power quality and efficiency in electrical plants using a three-phase series hybrid passive filter

The presence of harmonics introduces disturbances and losses in electrical systems that cause malfunctions and inefficiencies. In this paper, a passive three phase series hybrid power filter (PSHPF) is designed and applied in a commercial facility for reducing harmonics and distorced power generated by unbalanced linear/nonlinear loads, in this way the energy efficiency and the quality of power are improved. The filter is connected in series and can be switched on or off without interrupting the load operation. The filter inductance is suitably modified through some mutual inductances which are connected and disconnected using simple contactors. In this manner, additional losses related to the use of power electronic switches are not introduced. The proposed filter can reduce the typical critical parameter of power quality and can improve the overall efficiency of the system connected, from the power line to load. The simulation results show that proposed filter is capable of compensating harmonics and reactive power under unbalanced nonlinear load and/or non-ideal mains voltages.