Study on zero-sequence current distribution characteristics in Low Resistance Grounding mode

Low Resistance Grounding mode has been adopted in more and more megacities in China. The distribution characteristics of zero-sequence current in various cases of fault are fundamental for the proper operation of the zero-sequence current protection. Therefore, the distribution characteristics of zero-sequence current in the low resistance grounding mode are emphases of this paper. Based on Symmetrical Component Method, mathematical models and theory analysis were carried out for two-line single phase grounding fault of the same phase and of different phases. Thus, the mathematical expressions of zero-sequence current were derived. On this basis, quantitative analysis and comparison to the distribution characteristics of zero-sequence current in different cases were made, summarizing the differences between single-line and multi-line where ground faults take place. Finally, based on PSCAD/EMTDC, a great deal of simulating calculation for different cases of fault was done in order to verify the correctness of our theoretical analysis.

[1]  Mu Longhua,et al.  Ground-fault protection based on active component of zero-sequence current in resistance neutral grounded distribution systems , 2002, 2002 IEEE Region 10 Conference on Computers, Communications, Control and Power Engineering. TENCOM '02. Proceedings..

[2]  D. Paul,et al.  Low-resistance grounding method for medium voltage power systems , 1991, Conference Record of the 1991 IEEE Industry Applications Society Annual Meeting.

[3]  Hadi Saadat,et al.  Power System Analysis , 1998 .

[4]  Su Rui-xiong.  Study on Neutral Grounding Mode for 10kV Power Distribution Network , 2009 .

[5]  A. V. Wishtibeev.  About duration operate of resister for neutral grounding , 2003, 7th Korea-Russia International Symposium on Science and Technology, Proceedings KORUS 2003. (IEEE Cat. No.03EX737).

[6]  José Ramón Saenz,et al.  First resonant neutral grounding implantation in Spanish distribution system , 2001, 2001 IEEE Porto Power Tech Proceedings (Cat. No.01EX502).