Efficient time domain power quality state estimation using the enhanced numerical differentiation Newton type method

This contribution presents an efficient method for the time domain state estimation analysis in power systems. The proposed methodology evaluates the power quality state estimation using the enhanced numerical differentiation (END) method, which obtains the periodic steady state solution of a power network. This method exploits the half wave symmetry in the voltage and current waveforms. With the periodic steady state as initial condition, the estimation of harmonics and transients is evaluated by means of the Kalman filter (KF). This END-KF methodology determines the harmonic estimation under a time varying harmonics condition and the transient estimation due to fault transients. The results are compared against the Power Systems Computer Aided Design/Electromagnetic Transients Program including Direct Current (PSCAD/EMTDC) response.