In the small current grounding system of distribution network,the single-phase grounding fault isolation technology mainly includes power frequency parameter method,high frequency parameter method and external signal method,but there are prob-lems such as poor detectability,many interference factors and low fault tolerance rate.The current distribution and zero sequence ad-mittance phase Angle characteristics of the system are analyzed.The amplification effect of the different resistance values of the system neutral point on the fault current amplitude and the phase shift effect of the zero sequence admittance phase Angle are studied.In this paper,a method based on the resistive phase detection technique is proposed to realize the isolation of single-phase grounding fault in situ,which makes the fault characteristic measure have high detectability and the fault path have identifiability.The true type experi-ments show that the resistive phase protection is not affected by the interference factors such as the fault medium characteristic of the ground point,arc suppression coil,power flow direction and installation direction,and the protection resistance is as high as 3kΩ.The protection technology is mature,low cost,easy to realize,simple parameter setting,and can be widely popularized.
关键词
配电网/小电流接地系统/单相接地故障/动态电阻/相位保护/高阻接
Key words
distribution network/small current grounding system/Single-phase Grounding Fault/Dynamic resistance/phase protection/high resistance grounding
维普
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