Minutes of

Task Force on Nonstandard Lightning Voltages and

Task Force on Parameters of Lightning Strokes

7:00 p.m., Monday, 29 January 2001

Columbus , Ohio

 

            The joint meeting of the two Task Forces was attended by 13 members and guests.

 

            Prit Chowdhuri informed that a paper by the Task Force on Nonstandard Lightning Voltages will be written. It will incorporate: (i) tower response to steep-front waves, and (ii) volt-time characteristics of air gaps. Masaru Ishii has already submitted a report on item (i). John Anderson, Prit Chowdhuri and Enrico Cinieri have been working on item (ii). Tom McDermott submitted his work on item (ii) at the meeting. It will be distributed to the TF members for their comments.

 

            Prit Chowdhuri informed that the bibliography on parameters of lightning strokes (rev. 05, 01/2001) is now on the IEEE/PES website. Tom Short informed that the web page is at www.ieee.org/pes-lightning. The bibliography will be upgraded periodically.

 

            Prit has put together a task force paper: Parameters of Lightning Strokes: A Review. It is based on reports submitted by John Anderson, Prit, Mike Marz and Dave Nichols.The paper covers the return-stroke current, charge and integral of i2t. The draft was distributed to the Chairs of the two working groups on lightning and the lightning and insulator subcommittee. Prit has received a lot of feedback. The draft will be revised and distributed to the members of the task force.

 

It was the consensus at the meeting that the concave wavefront of the return-stroke current should be included. The concave wavefront has been incorporated in an IEC document. It was also mentioned that information on the lightning channel temperature be included.

 

            The validity of the field-test data was also discussed at the meeting. Prit mentioned that John Anderson, in a letter to Prit, suggested that lightning parameters should be investigated by totally different techniques, such as spectroscopy.

 

            Mike Marz later communicated that the assumption that the statistical distribution of the lightning parameters is global may be in error. Prit concurred. Similar to the ground flash density, the statistical distribution of the lightning parameters may be regional. It will be a significant contribution of the task force to prove or disprove the thesis that the statistical distribution of the lightning parameters is global.

 

            The meeting was adjourned at 8:50 p.m.

 

            Submitted by

 

 

            P. Chowdhuri

            31 January 2001