Contribution to the Theory of Stochastically Periodic Harmonics in Power Systems

A basic approach for quantitative evaluation of "Stochastically Periodic" harmonics effects on electrical equipment is presented. The main contribution of this paper is in defining and explaining a mathematical method which enables the estimation of the additional losses and the loss of life caused by stochastically periodic current/voltage harmonics. A practical case of N identical converters, randomly operated, is analyzed. The suggested method is applied to determine admissible levels of randomly periodic voltage harmonics for power capacitors.