Uncertainty Principle and Power Quality Sensing and Analysis in Smart Substation

Abstract

Different kinds of power quality can be sensed in a smart substation. Power quality sensing and analysis are basic functions of a smart substation for situation awareness. The uncertainty principle, which states that the time uncertainty and frequency uncertainty cannot be minimized simultaneously, is a bottleneck problem that undermines the faithfulness of sensing and confines the accuracy of analysis. This paper studies the influence of the uncertainty principle on the power quality monitoring issue in detail and solves the problem by ideal atomic decomposition (IAD). The new method employs a pair of time and frequency bases where the power quality waveform is sensed. Then, both time uncertainty and frequency uncertainty can be minimized simultaneously. The sensing process is realized by orthogonal matching pursuit (OMP). By simulated and field power quality tests with comparisons of developed methods, the new method can give faithful sensing and accurate analysis for various power qualities, and is validated as an effective power quality monitoring method in smart substations.

Investigation of power quality problems and harmonic exclusion in the power system using frequency estimation techniques

“…Finally, harmonic measurements and analysis enable the selection or creation of retrofitting mitigation countermeasures that are capable of alleviating the impacts of harmonics. " Cai, W., et al (2020) "investigated the impact of the uncertainty principle on the power quality monitoring issue, and the problem has been solved using perfect atomic decomposition (IAD). Whereas the new approach detects the power quality waveform, it is done so using a pair of time and frequency bases.…”

Effect Evaluation and Intelligent Prediction of Power Substation Project Considering New Energy

“…On the basis of implementing the principles of scientificity, systematic comprehensiveness, and practical feasibility and carefully combing the relevant theories of substation project implementation effect evaluation [23], combined with the background of high proportion of new energy access and the actual situation of substation projects, this paper constructs the evaluation index system of PSP implementation effect from the three perspectives of PSP technical level, PSP economy and PSP social benefit. The evaluation index system of PSP is composed of three first-level indexes and 15 s-level indexes, as shown in Table 1.…”