行业应用 Products

Upgrading and Renovation Project of a Low-resistance Grounding System

Date: 2016-05-24
Click: 28

 

In a city of Zhejiang, a system upgrading project from 10 kV to 20 kV has been completely implemented since 2011. Instead, the low-resistance grounding systems are applied. However, the earth fault tripping occurred frequently due to serious accidents arising from birds. The customers in the chemical fiber industry required a lot for the power supply quality, but short-time power failure had great impact on their product quality. Frequent tripping affected the normal industrial production of many enterprises. So the power supply authority often received lots of complaints.
 

Solution:

The original two low-resistance systems are upgraded into intelligent resistance grounding units, so that quick reactors can fulfill accurate compensation and eliminate earth faults in case of transient grounding.
         

Operation Effect:

Comparison of Six 20 kV Lines for Busbar Section #1 in this Substation before and after Renovation (between June 2011 and March 2012)
             

/


Before renovation (low-resistance grounding)


After renovation (intelligent multi-mode grounding)

/


June 2011


July 2011


August 2011


September 2011


From October 2011 to March 2012


Number of earth fault tripping

5

8

16

3

2

 

During low-resistance grounding, there were 32 earth fault trippings in four months. Since the operation of intelligent multi-mode grounding systems, such tripping occurred twice only in half a year. Apparently, such solution solved the frequent tripping problem and significantly improved the power supply reliability.

 

Related news
  • click: 98
    2016 - 05 - 23
    The 110 kV Dalong Substation in Dongguan has three main transformers and four busbar sections. Currently, the sixteen 10 kV outgoing lines (total length about 100 km) consist of overhead lines and cables. Three KD-XH01-315 / Model 10.5 quick arc suppression systems (including two smart detectors for the earth fault of Type DDS distribution network) are installed in this substation. In this way, the integrated earth fault solution is available for the 10 kV distribution network.    It had operated for more than three years from October 2002 to the beginning of 2006. In the first year, only line selection rather than automatic trip was tentatively conducted as planned. The automatic trip has been enabled since January 7, 2004, with 10s as provisional trip time.   ...
  • click: 34
    2016 - 05 - 23
    Total Buck Transformer Substation 1# of Fujian Refining & Chemical Co., Ltd. is a 110 kV substation consisting of two 110 kV main transformers and two 6 kV busbar sections. It has secondary substations respectively for treated water, polypropylene, coking, hydrogenation, constant voltage, catalysis and circulating water. The 6 kV grid system is a resonance grounding system with the neutral point earthed via an arc suppression coil. The earth fault line selection devices for the microcomputer low current system are used for the single-phase grounding protection of each outgoing line circuit. Since their operation in 1997, the original air gap inductance regulation air-suppression system and its line selection devices have shown many problems, mainly including:   The grid capac...
  • click: 25
    2016 - 05 - 23
    Compensation capacity: -8 MVar to +8 MVarSystem voltage: 10 kVProject feature: an outdoor cabinet-type unit capable of being interconnected with the regional automatic voltage control (AVC) systemSystem composition: 8 MVar SVGCompensation scheme:   In normal cases, the system adopts the power factor of the 10 kV busbar as control target. In case of system failure, it will get into the overload forced compensation state for accelerating the recovery of network voltage.   A top layer controller is available for access to the substation monitoring system and the regional AVC system.
  • click: 32
    2016 - 05 - 23
  • click: 35
    2016 - 05 - 24
    Scheduling Data Interconnected System of Shanghai Electric Power Co., Ltd.Scheduling Data Interconnected System of Hubei Electric Power CompanyProvincial Real-time Scheduling Data Interconnected System of Hunan Electric Power CorporationData Interconnected System for the Concentrated Control Substation of Shanghai Electric Power Co., Ltd.Data Interconnected System of Hangzhou Municipal Electric Power BureauProduction Information Integration System of Huanggang Electric Power Company in Hubei ProvinceIntegrated Scheduling Data Platform of Shanghai Electric Power Co., Ltd.Integrated Scheduling Data Platform of the Lancangjiang Centralized Control CenterIntegrated Scheduling Data Platform of Hunan Electric Power CorporationIntegrated Scheduling Data Platform of Chongqing Electric Power Compan...
  • click: 26
    2016 - 05 - 24
    Online Monitoring System for HV Equipment State at the Booster Station of the Fengcheng Power Plant Intelligentized Reconstruction Project of the Fanchang Substation of Anhui Electric Power Company Intelligent Substation State Monitoring System for the Qiantang Substation in Hangzhou Intelligent Substation State Monitoring System for the Shanghai Mengzi Substation Integrated Monitoring System for the Xuhang Substation of East China Grid Company Limited Intelligent Substation State Monitoring System for the Data Interface Development of Guizhou Power Grid Co., Ltd. Intelligent Substation State Monitoring System of Gansu Electric Power Company Intelligent Substation State Monitoring System for Guizhou Power Grid Company for Online Substation Data Access into Level II Platform Intelli...
Copyright ©2005 - 2017 Guangzhou Zhiguang Electric Ltd.