A Novel Algorithm for Accurate Frequency Measurement Using Transformed Consecutive Points of DFT

A novel algorithm based on discrete Fourier transform (DFT) to estimate the frequency of power system is proposed. The algorithm that we called transformed discrete Fourier transform (TDFT) involves transforming consecutive points of DFT of voltage signals to reduce the leakage components. The algorithm has the following merits: It is immune to inter-harmonics as well as harmonics; it has simple and easy implementation; and it has good performance both in steady and dynamic states. What is more, it can keep high precision in a very wide frequency deviation range, for example, 40-60 Hz. Simulation experiments validate this algorithm can track power system frequency precisely.

[1]  Adly A. Girgis,et al.  Optimal Estimation of Voltage Phasors and Frequency Deviation Using Linear and Nonlinear Kalman Filtering: Theory and Limitations , 1984, IEEE Power Engineering Review.

[2]  J. Rezmer,et al.  Real-time determination of power system frequency , 1996, Quality Measurement: The Indispensable Bridge between Theory and Reality (No Measurements? No Science! Joint Conference - 1996: IEEE Instrumentation and Measurement Technology Conference and IMEKO Tec.

[3]  Vladimir Terzija,et al.  Voltage phasor and local system frequency estimation using Newton type algorithm , 1994 .

[4]  R. Grondin,et al.  Fast adaptive schemes for tracking voltage phasor and local frequency in power transmission and distribution systems , 1991, Proceedings of the 1991 IEEE Power Engineering Society Transmission and Distribution Conference.

[5]  M.S. Sachdev,et al.  Kalman Filtering Applied to Power System Measurements Relaying , 1985, IEEE Transactions on Power Apparatus and Systems.

[6]  C. W. Liu,et al.  A Precise Calculation of Power System Frequency , 2001, IEEE Power Engineering Review.

[7]  Zhongxing Geng,et al.  The algorithm of interpolating windowed FFT for harmonic analysis of electric power system , 2001 .

[8]  M. S. Sachdev,et al.  Off-Nominal Frequency Measurements in Electric Power Systems , 1989, IEEE Power Engineering Review.

[9]  W. L. Peterson,et al.  Adaptive estimation of power system frequency deviation and its rate of change for calculating sudden power system overloads , 1990 .

[10]  Adly Girgis,et al.  A Quantitative Study of Pitfalls in the FFT , 1980, IEEE Transactions on Aerospace and Electronic Systems.

[11]  P. Djurić,et al.  Frequency tracking in power networks in the presence of harmonics , 1993 .

[12]  M. Sachdev,et al.  A Least Error Squares Technique For Determining Power System Frequency , 1985, IEEE Transactions on Power Apparatus and Systems.

[13]  J. Thorp,et al.  A New Measurement Technique for Tracking Voltage Phasors, Local System Frequency, and Rate of Change of Frequency , 1983, IEEE Transactions on Power Apparatus and Systems.