Unbalance analysis for electrical power systems in the presence of harmonics and interharmonics

A new method to evaluate the unbalance for electrical power systems in the presence of harmonic and interharmonic distortion is presented. A new unique transformation matrix able to extract the balanced, the first unbalanced, and the second unbalanced components suitable for all of the harmonic and interharmonic orders is introduced. The decomposition presented allows evaluating the quantities defined in IEEE Standard 1459-2010 taking into account unbalances produced by harmonics and interharmonics and extending some important definitions to signals characterized by interharmonic distortion.