SYNAPS - LV Fault Location Innovation

Many faults on the low voltage (LV) networks are caused by gradual degradation of underground cables, allowing water ingress. This causes an arc, which often vaporises the water and clears the fault. These faults are known as ‘transient faults’ or ‘pecking faults’ and are invisible to the Distribution Network Operators (DNO) and customers. As the cables degrade further, these faults may be sufficient to cause fuses to blow, causing power disruption. When the fuse is replaced, the fault will appear to have cleared. However, the underlying fault will remain, causing the fuse to blow again. Eventually, the transient faults become permanent and require major maintenance work.

Current DNO practice is mostly reactive as LV underground cable faults are difficult to detect, locate and fix. LV underground faults are only discovered after fuses start to rupture and disrupt supply. These faults present a significant proportion of LV fault maintenance costs and customer minutes lost (CML).  

SYNAPS (Synchronous Analysis and Protection System) innovation is aimed at transforming LV underground cable fault management for LV electricity networks by locating early transient faults before a fuse rupture.

The solution consists of capture units placed in the LV network, which continually monitor the LV feeder cables, detect the fault events, and share the event information with our software server for further analysis. The technology uses sophisticated management software with advanced statistical signal processing and machine learning algorithms to identify LV cable faults, including early transient faults.

It is a compact solution for monitoring LV underground networks to provide real time detection, classification, and location of LV cable faults. 

This early information on developing underground cable faults will give the DNO the opportunity for proactive and preventative network maintenance. The technology will enable DNOs to make significant reductions in the cost of LV network operation, replacing high cost and high disruption operations with automated asset management procedures.

Network Innovation Allowance (NIA) Projects

SYNAPS projects, funded by NIA, seek to trial and validate the innovative technology for LV fault detection, classification, and location. Scottish and Southern Energy Networks (SSEN) and UK Power Networks (UKPN) DNO are innovation partners in these projects.

Stage 1 [Jun 2018 – Nov 2019]: 

Technology validation in Power Network Demonstration Centre (PNDC) network successfully demonstrated:

  • Detection of a transient fault event that does trigger network protection
  • Fault type classification: phase-to-phase, phase-to-neutral
  • AI algorithm classification of a fault to a main cable or a spur

Stage 2 [Dec 2020 – Jul 2022]:

The success of the first SYNAPS trials led to funding for a second project to develop the technology further. Stage 2 objective is to improve the AI algorithms for improved location detection and accuracy and develop the technology towards business-as-usual readiness. Technology validation is being done on live LV networks to:

  • Evaluate solutions in interconnected mesh networks
  • Optimise the network calibration procedure
  • Improve AI algorithms with data from a wider range of circuits
  • Demonstrate cable joint fault location
  • Define of IT System connection specification