Stochastic Assessment of Harmonic Propagation and Amplification in Power Systems Under Uncertainty

The time-varying harmonics in power systems are not only caused by the stochastic harmonic emissions from different types of harmonic sources, but also the uncertain harmonic response of the system. This paper aims to reveal the impact of the latter and presents a stochastic assessment technique to study the harmonic propagation and amplifications in power systems. To achieve this, systematic indices are defined to quantify the harmonic propagation and amplification characteristics of the system. Potential system uncertainties are then categorized using aleatory and epistemic uncertainties. As a result, both the time-varying and epistemic randomness can be characterized. Finally, the stochastic behavior of the harmonic propagation and amplification is studied using the Monte Carlo simulation technique. Moreover, the impact of load modelling method on the randomness of harmonic propagation and amplification has been investigated, raising awareness to the importance of careful selection and validation of the load modelling on harmonic studies. Extensive case studies confirm the usefulness and effectiveness of the proposed method.