Research On Hybrid Grounding Run Of10kV Distribution Network

The neutral grounding mode of the distribution is a comprehensive technical problem which associated with stability, economic, security and other various aspects. The neutral grounding mode of the lOkV network involved of no grounding, grounding by resonance or reactance grounding, different grounding operation modes have their advantages and disadvantages.This paper focuses on the special issues about hybrid running of resonant grounding and low resistance grounding.Firstly, in this paper, the methods of distribution netral grounding are to be introduced and analyzed in theorys. Resonant grounding and low resistance grounding are focused on with principle analysis and theoretical calculations. The effects about electrical quantities of system are investigated with different transition resistance for single-grounding fault. Different operating characteristics are summarized. The theoretical analysis and simulation are compared.Secondly, analyzes the distribution network under single-phase fault neutral grounding via arc suppression coil and the characteristics of low resistance grounding system, describes the principle of protection and protection scheme, focused on low resistance grounding system configuration of the principle of conservation programs.Thirdly, with practical parameters of two substations as the basis, a hybrid grounding model was established by systematic simulation software PSCAD, The impact of different fault location in hybrid grounding system is studied, and the co-operation of two low resistance grounding system is studied, get some characteristics of the hybrid grounding systems. The paper put forward proposals and some improvements of protection scheme to run the hybrid grounding system.Finally, the paper makes a associated design about the actual renovation project of Luo Jiazui transformer substation. Small resistor and Z transformer are selected. Protection program is configured. These works get a strong reference about extensive use of low resistance grounding. The paper has a strong engineering application value.