Unbalance and harmonic distortion assessment in an experimental distribution network

• Experimental validation of two quality indices: LCI and UCR.
• Load Characterization Index (LCI) identifies linear and non-linear loads.
• Unbalance Current Ratio (UCR) assigns unbalance load and source responsibility.
• LCI identifies capacitors as linear loads.

The identification of voltage and current harmonic distortion and voltage unbalance sources is one of the main problems in electric distribution systems. In order to overcome it, in this paper the use of two novel indices is proposed. On the one hand, the Load Characterization Index (LCI) is suggested to calculate the harmonic distortion introduced by the load. This index identifies linear and non-linear loads in the power systems. On the other hand, the Unbalance Current Ratio (UCR) is suggested to assign the responsibility for system unbalance to load and source sides. Both indices can be calculated only from the measurement of the current at the input of the load and the voltage at the Point of Common Connection (PCC). The main objective of this paper is to test the performance of these two indices on an experimental three-phase electrical network. In order to do that, several experimental tests have been considered.