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This paper develops a signal processing, time-frequency analysis-based analytic solution to locate transient capacitor switching disturbances. The flow of transient disturbance energy caused by the capacitor switching is determined by the time and frequency localized phase difference. Cross time-frequency analysis provides time- and frequency-localized phase difference between the transient voltage and current disturbance waveforms which determine the direction of transient disturbance energy flow. The time and frequency localization properties of the proposed scheme allows one to expand the application to complicated power distribution systems without knowledge of system parameters, capacitor size, and configuration. The proposed scheme has been verified by the Electromagnetic Transients Program simulation for all possible spatial locations of the capacitor switching. [ABSTRACT FROM AUTHOR]

This paper develops a method using transient voltage and current measurements at the substation to determine which capacitor in a multicapacitor feeder switched on to cause a measured transient. The procedure is based upon time-domain analysis where a backward Kalman filter estimates the initial voltage of all feeder capacitors, and those estimates indicate which capacitor switched. The result is an automated procedure that can help electric utilities determine if their capacitors are switching properly, and also help pinpoint the source of capacitor switching-related power-quality problems. [ABSTRACT FROM AUTHOR]

Presents the use of rule-based method and hidden Markov model (HMM) in classifying the power distribution line disturbances. Function of the rule-based method and HMM; Classification on the types of actual recorded power distribution disturbances by the methods; Classification rate of the methods for actual disturbance events tested.

Presents a technique for determining power quality disturbances sources location. Influence of capacitor switching and voltage on power disturbance; Importance of energy flow and peak instantaneous power of both capacitor and voltage sag in determining disturbances location; Application of the technique in computer-simulated and actual disturbances.

Investigates the effect of supply voltage harmonics on the excitation current of a typical 25 kilovolt-ampere single-phase distribution transformer. Time domain waveform; Harmonic components of the excitation current; Phase angles of the supply voltage harmonics; Third harmonic component in the supply voltage.

Responds to comments on an article appearing in the January 2000 issue of 'IEEE Transactions on Power Delivery,' which dealt with the features of power distribution quality events. Application of wavelet features; Ability of wavelet transform to distinguish between internal and external faults in transformers.