Improved Fundamental Frequency Estimator for Three-Phase Application

This letter reports a digital signal processing based frequency estimation technique that relies on the storage of fundamental three-phase grid voltage samples. Unlike phase-locked loop algorithms, the proposed algorithm does not require the phase error information when estimating the grid frequency...

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Detalles Bibliográficos
Autores: Kumar Verma, Anant, Jarial , Raj Kumar, Rao Ungurala, Mohan, Roncero Sánchez-Elipe, Pedro Luis
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/40263
Acceso en línea:https://hdl.handle.net/10578/40263
Access Level:acceso abierto
Palabra clave:Digital signal processing
frequency estimation
moving average filter (MAF)
three-phase grid voltage
Descripción
Sumario:This letter reports a digital signal processing based frequency estimation technique that relies on the storage of fundamental three-phase grid voltage samples. Unlike phase-locked loop algorithms, the proposed algorithm does not require the phase error information when estimating the grid frequency. Moreover, only four consecutive samples of the fundamental orthogonal components are required in order to estimate the deviation in the grid frequency. The proposed scheme is facilitated with an inherent nonadaptive comb filtering behavior in order to reject the dc offset and harmonics while attaining a good immunity to voltage sag and the fundamental negative sequence component. Additionally, the off-nominal harmonic rejection capability of the proposed frequency estimator is enhanced by using a postfiltering method. The experimental validations reported in this study demonstrate that the proposed frequency estimator is suitable for three-phase grid applications.