Current harmonic estimation techniques based on voltage measurements in distribution networks

Current harmonics generated by power electronic devices and other nonlinear loads have been a major concern in distribution systems due to quality and efficiency deterioration. To find effective solutions to reduce the level of these current harmonics, their magnitude and phase angle need to be first measured. Adding current sensors is not a practical solution at the system level due to cost and technical concerns. Consequently, a harmonic current estimation method based on only voltage measurement is proposed in this paper. The method can be used in smart power electronics systems to find optimum conditions for current harmonic compensations. Analytical calculations are presented for both single- A nd multi-unit systems followed by simulation results to confirm the validity of the proposed method.