Phasor Estimation of Transient Electrical Signals Composed of Harmonics and Interharmonics

Numerical relays have become essential tools for carrying out the protection and surveillance tasks of electrical power systems. These implement their functions from phasors network signals, estimated by digital processing using filters. Digital filters must meet certain requirements, such as providing a fast effective response to increasingly complex transient signals made up components that make estimation process difficult. In addition decreasing exponential (decaying dc offset), harmonics, signal noise, it be added interharmonic in recent years acquired great relevance, mainly because increase non-linear loads extensive use electronic The presence these causes poor most implemented today. This article presents design new filter, C-CharmDF (Cleaned Characteristic Harmonic Filter) phasor on noisy with components, interharmonics. A detailed study was carried severe situations stationary signals. It found method can suitable both fault location system functions.