Reference wave generation in dynamic voltage restorers by use of PQR power theory

Dynamic voltage restorer (DVR)s are known as effective and economic means to compensate for voltage sags and swells. This paper proposes a novel method to generate reference waves synchronized with the grid whether or not the line voltages are distorted by a fault. The proposed reference wave generator (RWG) looks for the normal voltage waveforms in the grid from the corrupted line voltages and synthesizes the expected positive sequence reference waves for DVRs. There is no transient problem on the generated reference waves when the line voltages are distorted by faults. Experimental results verified the proposed theory very well.

[1]  C. Grigg,et al.  Predicting and preventing problems associated with remote fault clearing voltage dips , 1989, Conference Record. Industrial and Commercial Power Systems Technical Conference.

[2]  M. J. Samotyj,et al.  Voltage sags in industrial systems , 1991, Conference Record. Industrial and Commercial Power Systems Technical Conference 1991.

[3]  D. S. Dorr.  Point of utilization power quality study results , 1994 .

[4]  J. J. Stanislawski.  National Power Laboratory power quality study 1972 to 1979 revisited , 1995, Proceedings of INTELEC 95. 17th International Telecommunications Energy Conference.

[5]  M. D. Stump,et al.  The role of custom power products in enhancing power quality at industrial facilities , 1998, Proceedings of EMPD '98. 1998 International Conference on Energy Management and Power Delivery (Cat. No.98EX137).

[6]  D. O. Koval,et al.  Canadian national power quality survey: frequency and duration of voltage sags and surges at industrial sites , 1998 .

[7]  G. Joos,et al.  Three-phase static series voltage regulator control algorithms for dynamic sag compensation , 1999, ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465).

[8]  John Godsk Nielsen,et al.  Control strategies for dynamic voltage restorer compensating voltage sags with phase jump , 2001, APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181).

[9]  Birgitte Bak-Jensen,et al.  Instantaneous power compensation in three-phase systems by using p-q-r theory , 2002 .