Application of Enhanced Phase-Locked Loop System to the Computation of Synchrophasors

作者：Karimi Ghartemani Masoud^*; Ooi Boon Teck; Bakhshai Alireza

来源：IEEE Transactions on Power Delivery, 2011, 26(1): 22-32.

DOI：10.1109/TPWRD.2010.2064341

• enhanced phase-locked loop (EPLL)
• IEEE Std. C37.118-2005
• phasor measurement unit (PMU)
• synchrophasor
• wide-area measurement systems (WAMS)

This paper introduces the application of an enhanced phase-locked loop (EPLL) system to the estimation of synchrophasors in a phasor measurement unit (PMU). The major concern is accurate estimation within off-nominal frequency operation of the system. The well-known technique based on discrete Fourier transform (DFT) can provide accurate estimation of the phasors in a three-phase balanced system. However, the negative-sequence component causes errors to the DFT estimates. The DFT cannot accomplish this task in a single-phase system. The EPLL is shown to be a solution for those shortcomings of the DFT technique, both in single-phase and in unbalanced three-phase systems, at the expense of some more complicated structure. Extensive steady-state and dynamic tests are performed and the results are presented and discussed.

• 出版日期2011-1