Accurate parameter estimation for unbalanced three-phase system

ScientificWorldJournal. 2014:2014:539420. doi: 10.1155/2014/539420. Epub 2014 Aug 4.

Abstract

Smart grid is an intelligent power generation and control console in modern electricity networks, where the unbalanced three-phase power system is the commonly used model. Here, parameter estimation for this system is addressed. After converting the three-phase waveforms into a pair of orthogonal signals via the α β-transformation, the nonlinear least squares (NLS) estimator is developed for accurately finding the frequency, phase, and voltage parameters. The estimator is realized by the Newton-Raphson scheme, whose global convergence is studied in this paper. Computer simulations show that the mean square error performance of NLS method can attain the Cramér-Rao lower bound. Moreover, our proposal provides more accurate frequency estimation when compared with the complex least mean square (CLMS) and augmented CLMS.

MeSH terms

  • Artificial Intelligence*
  • Computer Simulation*
  • Nonlinear Dynamics
  • Power Plants*
  • Renewable Energy