A New Method to Monitor the Primary Neutral Integrity in Multi-Grounded Neutral Systems

Xiangmin Xie, Yuanyuan Sun, Xun Long and Bingwei Zhang
Additional contact information
Xiangmin Xie: School of Electrical Engineering, Shandong University, Jinan 250061, China
Yuanyuan Sun: School of Electrical Engineering, Shandong University, Jinan 250061, China
Xun Long: FortisAlberta, Calgary T3K6E8, AB, Canada
Bingwei Zhang: School of Electrical Engineering, Shandong University, Jinan 250061, China

Energies, 2017, vol. 10, issue 3, 1-18

Abstract: In the three-phase four-wire system, there are usually multiple grounding points in the primary neutral line due to safety and economic considerations. The rising “neutral to earth voltage (NEV)” caused by a broken primary neutral can threaten the safety of nearby facilities and humans; therefore, the integrity of the primary neutral conductor is of vital importance for the multi-grounded neutral (MGN) system. In this paper, a new passive method is proposed to monitor the integrity of the primary neutral line in the MGN system. The method is based on the measured voltage and current data at the service transformer, and there is no need to install any signal generators. Therefore, it causes no disturbance to the utility and customer. In the paper, the equivalent analysis circuit is established and a new parameter is proposed to reflect the neutral condition. The value of the parameter is estimated based on the measured data, and then, the equivalent impedance of the primary neutral groundings can be obtained. On the other hand, the impedance value for the primary neutral under normal operating conditions can be estimated based on the derived analytical formulas. By comparing the monitored primary neutral impedance with its normal value, the broken neutral condition in the primary system can be detected. Different primary neutral broken cases are analyzed in the paper based on the Monte Carlo simulation. The results indicate that the integrity condition in the primary neutral can be accurately monitored by the proposed method.

Keywords: primary neutral integrity; multi-grounded neutral (MGN) system; neutral integrity detection; passive method (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2017
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/10/3/380/pdf (application/pdf)
https://www.mdpi.com/1996-1073/10/3/380/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:10:y:2017:i:3:p:380-:d:93291

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().