Season 5 Challenges

Reward- INR 5,00,000 | Opening Date: 19 NOV 2018  |  Closing Date: 19 FEB 2019   
Ferous Oxide

Electrical power is often distributed via underground cables as an alternative to overhead cables since underground cables have a longer service life, are less dangerous to people and contribute positively to the aesthetic planning of a town or city.

At present we have ~ 850 Km of high-tension (33 KV or 6 KV) underground network of various sizes distributed in entire city at a depth of 0.7-1 meter from the ground surface. The type of cables deployed are:

  • PILCA (Paper Insulated Lead Cable Armour) cable:  ~255 Km having an average age of more than 60 years
  • XLPE (Cross-Linked Polyethylene) Cable:  ~ 595 Km having an average life of 15 to 20 years

The data shows that, on an average,13-15 breakdowns of HT cables happen every year due to cable joint failures. Due to these breakdowns, reliability indices get affected, and also results in customer dissatisfaction.

Currently, there is no mechanism to assess the health of the cables and to predict their remaining life. Also, the exact location of the insulation weakness is not known. Carrying out Insulation Resistance test measurements for every cable does not help solve the problem as it neither reflects accurate result nor is it feasible due to shutdown issues and manpower requirements.

The main challenge here is to attain an online assessment of the cable health and to determine their useful remaining life along with the location of weak joints, without having to undertake shutdown mechanism.

Future State:

  • Proactive health assessment of cable and finding the weak cable joints. Based on the findings, actions will be taken to either arrest the fault location or to replace the cables.
  • This will help in reducing SAIDI (System Average Interruption Duration Index), improving reliability indices and customer satisfaction.

Success Criteria:

Must have:

  • Health assessment (number of years/days/months of useful life left)
  • Location of fault – weak joints and their locations

Nice to have:

  • To assess the health without power shutdown
  • To avail the data on a continuous basis.
  • Handheld portable type machine is preferred.

Have any query or need more clarification about this challenge?