Thursday, August 23, 2012

Analysis of Indian Power Outage end of July 2012 published the other day

Guess you remember the biggest blackout that ever happened in India end of July 2012 – leaving several 100 Million people without power for some time!

A first comprehensive report has been published:

REPORT OF THE ENQUIRY COMMITTEE
ON GRID DISTURBANCE
IN NORTHERN REGION

16th AUGUST 2012
NEW DELHI

What happened on the 30th and 31st of July? A lot!

The Substation Protection Automation systems, for example, all over worked quite well. The report lists 100+ tripping events of protection devices !! That means many lines were taken out of service in order to protect the lines, switches, transformers, generators, … Before a line is damaged by overload, it is disconnected from the power flow – it operates like a “smart” fuse. Indian people should be thankful that most protection functions worked well.

My summary of the report is:

  • Experts figured out that the power delivery systems in India are very huge and very complex.
  • Investments to maintain and operate these complex systems and to keep them stable with the growing demand were far too low.
  • A list of short, medium and long term actions are suggested to prevent such events in the future.

One issue regarding communication is very interesting, the report states that: “The existing communication network should be maintained properly. RTUs and communication equipments should have uninterrupted power supply with proper battery back up so that in case of total power failure, supervisory commands & control channels do not fail.

My personal experience in the early 1970s was that battery back up systems are often badly maintained. I was responsible for a brand-new centralized fire alarm system with 6,500 manual fire alarm detectors. The control system crashed at least once a week. As a young man (21) I could not accept that the manufacturer of that huge fire protection system did not act properly to investigate what the problem was; the customer was quite angry. I was too young to do my own deep inside analysis of the problem. I didn’t even have the instruments to do it. So, I quit my job and went back to school and university … and came back to the same company after 7 1/2 years (and father of four kids). I started as an engineer in 1981 – in the area of communication for process automation (IEEE 802.3 Ethernet, IEEE 802.4 Token Bus, MAP, Profibus, … ).

Later somebody reported to me what the cause of the problems of the centralized system was: BADLY MAINTAINED Back-Up Power Supply before it was installed! The batteries were stored in the basement for one year – without anybody keeping an eye on it. The physical laws hit back after the batteries were installed.

A system is as weak as its weakest link.

I guess the results of the investigation are not new. Many engineers have warned all over all the time that more investment is needed to keep the lights on.

Download the complete 70 page report [pdf, 830 KB].

1 comment:

Unknown said...

Good story! I made allmost the same experience. Communication technology often is underestimated by responsible Managers.
Hans Kranz