Phase Estimation Method for Power System Based on Complex Adaptive Neural Network

doi:10.12068/j.issn.1005-3026.2017.01.002

Abstract

Abstract: Aiming at the difficulty of grid phase detection under non-ideal voltage caused by unbalanced voltage and frequency fluctuation， a phase estimation method was proposed for power system based on complex adaptive neural network. On the basis of neural network model of non-ideal grid voltage， the weight update method of complex least mean squares to the process of weight update procedure of neural network was introduced. Then the weights of neural network were used to calculate the phase. To trace the frequency of grid， a frequency tracing unit was designed and it was proved to be convergent. The simulation and experiment results demonstrate that the proposed method is able to estimate the phase rapidly and precisely under non-ideal voltage conditions.

Key words: phase estimation, neural network, unbalanced voltage, frequency tracing, grid phase

CLC Number:

TM76

LI Yun-lu， WANG Da-zhi， NING Yi， HUI Nan-mu. Phase Estimation Method for Power System Based on Complex Adaptive Neural Network[J]. Journal of Northeastern University Natural Science, 2017, 38(1): 6-10.

References

[1]Baradarani F，Mohammad R.Zadeh D，et al.A phase-angle estimation method for synchronization of grid-connected power-electronic converters［J］.IEEE Transactions on Power Delivery，2015，30(2):827-835.
[2]Du S，Liu J，Lin J，et al.A novel DC voltage control method for STATCOM based on hybrid multilevel H-bridge converter［J］.IEEE Transactions on Power Electronics，2013，28(1):101-111.
[3]Rady Y A，Mohamed I，Saadany F E.A robust natural frame based inter facing scheme for grid-connected distributed generation inverters［J］.IEEE Transaction on Energy Conversion，2011，26(8):728-736.
[4]Xia Y L，Douglas S C，Mandic D P.Adaptive frequency estimation in smart grid applications:exploiting non circularity and widely linear adaptive estimators［J］.IEEE Signal Processing Magazine，2012，29(5):44-54.
[5]Roncero-Sanchez P，Garcia X D T，Torres A P，et al.Fundamental positive-and negative-sequence estimator for grid synchronization under highly disturbed operating conditions［J］.IEEE Transactions on Power Electronics，2013，28(8):3733-3746.
[6]Golestan S，Monfared M，Freijedo F D.Design-oriented study of advanced synchronous reference frame phase-locked loops［J］.IEEE Transactions on Power Electronics，2013，28(2):765-778.
[7]Liu B Q，Zhuo F，Zhu Y X，et al.A three-phase PLL algorithm based on signal reforming under distorted grid conditions［J］.IEEE Transactions on Power Electronics，2015，30(9):5272-5283.
[8]Wang L，Jiang Q R，Hong L C，et al.A novel phase-locked loop based frequency detector and initial phase angle detector［J］.IEEE Transactions on Power Electronics，2013，28(10):4538-4549.
[9]Safayet A，Husain I，Elrayyah A，et al.Grid harmonics and voltage unbalance effect elimination for three-phase PLL grid synchronization algorithm［C］//Energy Conversion Congress and Exposition(ECCE).Denver，2013:3299-3304.
[10]Dini D H，Mandic D P.Widely linear modeling for frequency estimation in unbalanced three phase power system［J］.IEEE Transactions on Instrumentation and Measurement，2013，62(2):353-363.
[11]Xia Y L，Blazic Z，Mandic D P.Complex-valued least squares frequency estimation for unbalanced power systems［J］.IEEE Transactions on Instrumentation and Measurement，2015，64(3):638-648.
[12]Qasim M，Kanjiya P，Khadkikar V.Artificial-neural-network-based phase-locking scheme for active power filters［J］.IEEE Transactions on Industrial Electronics，2014，61(8):3857-3866.
[13]Sadinezhad I，Agelidis V G.Real-time power system phasors and harmonics estimation using a new decoupled recursive-least-squares technique for DSP implementation［J］.IEEE Transactions on Industrial Electronics，2013，60(6):2295-2308.
[14]Haykin S.Adaptive filter theory［M］.Edinburgh:Pearson Education Limited，2013.
[15]Sadinezhad I，Joorabian M.A novel frequency tracking method based on complex adaptive linear neural network state vector in power systems［J］.Electric Power Systems Research，2009，79(8):1216-1225.
[16]Rodriguez P，Teodorescu R，Candela I，et al.New positive sequence voltage detector for grid synchronization of power converters under faulty grid condition［C］//Power Electronics Specialists Conference (PESC’06).Barcelona，2006:1-7.