Harmonic/interharmonic estimation using standard deviation assisted ESPRIT method
ISSN: 0332-1649
Article publication date: 14 October 2021
Issue publication date: 11 November 2021
Abstract
Purpose
This paper aims to accurately estimate harmonics/interharmonics in modern power system. There are several high spectral resolution techniques that have been in use for several years like Estimation of Signal Parameters via Rotational Invariance Technique (ESPRIT), Prony methods, etc. but these techniques require prior knowledge of number of modes present in the signal. Model Order (MO) estimation techniques have to make a trade-off between accuracy and their speed i.e., computational burden. Therefore, there is always a requirement of a technique that is fast as well as accurate.
Design/methodology/approach
The proposed standard deviation (SD) method eliminates the requirement of energy validation test and analyses the distribution pattern, i.e. standard deviation of eigenvalues to identify the number of modes present in the signal. Signal is reconstructed using estimated modes and reconstruction error is obtained to show accuracy of the proposed estimation.
Findings
Six test synthetic signals as well as one practical signal have been taken for validating the proposed method. The paper shows that proposed methodology has a better accuracy compared to modified exact model order (MEMO) method in high noise environment and takes very less computation time compared to the exact model order (EMO) method.
Practical implications
The proposed method has been practically implemented for harmonic/interharmonic analysis at a sewage treatment plant at GIFT City, Gujarat, India. Apart from this the proposed method is modeled in python-based tool and is run into low-cost Raspberry Pi like hardware to create an onsite as well as remote monitoring device.
Originality/value
SD-based approach for model order estimation is novel to this area. Further, the proposed method is compared with EMO and MEMO under varying noise conditions to check for accuracy and estimation time.
Keywords
Acknowledgements
The authors would like to thank Federal Ministry of Education and Research (BMBF, Germany) and Department of Science and Technology (DST, India) for funding the research and development activities of the project. This work is being carried out for an ongoing research project called ECO-WET, under the flagship of IGSTC (Indo-German Science and Technology Centre). Authors would also like to thank GIFT City, Gujarat, India, for providing the testbed for validation and analysis purposes.
Conflict of interest statement: The authors declare that there is no known conflict of interest of any kind with the work reported in this paper.
Citation
Srivastava, A.K., Tiwari, A.N. and Singh, S.N. (2021), "Harmonic/interharmonic estimation using standard deviation assisted ESPRIT method", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 40 No. 6, pp. 1067-1083. https://doi.org/10.1108/COMPEL-03-2021-0108
Publisher
:Emerald Publishing Limited
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